# Dummy Question #007: What's your flow?



## niko (Jan 28, 2004)

http://www.adaeuro.com/allestimento_eng.asp?all=4

The first paragraph (under the red "Filtration System" header) says something interesting. Certainly not what I have been doing since I started in the hobby. Yes, you can have clean tanks with much less water movement. Yes, you can have clean tanks with tiny filters. Or no filter at all.

So why would ADA suggest such humongous flow rates? And such monster sized filters?

They want me to put a 5 gallon sized filter under my 55 gal. tank. The size of one of those orange Home Depot buckets that is! And run a 550 gph pump on it. Keep in mind that they must mean actual flow in the tank because their stainless steel canister filters are equipped with pumps that are nothing like the flimsy pumps we have in our plastic filters. Their flow is not reduced that much from a clogged filter media or from the distance filter to tank. So the pump rating on their filter is very much what you will get coming out of the outflow.

But let's make things simple:

*What is your:
- tank size
- filter volume
- the rating of your filter pump in GPH?
*

--Nikolay


----------



## niko (Jan 28, 2004)

My answers:

Tank 1
- 160 gal. tank
- 8 gallons filter volume
- 230 gph flow

Tank 2
- 55 gal. tank
- 2 gallons filter volume
- 150 gph flow

Now, let's be clear here - the additional flow from powerheads, fish movement, hand movements in the tank, ladles, paddles etc. do not count.

--Nikolay


----------



## grak70 (Jan 5, 2010)

- 75 gal. tank
- 1.7 gallons filter volume
- 160 gph (measured, 325 rated)

I'm a worse heretic than you apparently.

I have been greatly enjoying the dummy questions. I want to venture a guess as to the answer, but I'll be patient and just say what I think the key concept is:

Concentration. Specifically, keeping concentration of everything in the water column as low as possible.


----------



## Bert H (Mar 2, 2004)

Tank size: 50 gal
Filter volume: don't know
Pump rating: 300gal/hour, which I seriously doubt having to go through in-line reactor and heater.

A couple of things I found interesting in that link. First, they use activated carbon, something we typically suggest not doing, unless you're removing some medications. Second was this:



> TURMALINE F: a semi-precious mineral with the property of releasing important metals useful to plants and neutralizing harmful electromagnetic waves mostly generated by the filter pump


_'Harmful electromagnetic waves????'_:spy:


----------



## Tex Gal (Nov 1, 2007)

Tank size: 125g
Filter volume: 18L
Pump rating: 950 gph


----------



## grak70 (Jan 5, 2010)

> 'Harmful electromagnetic waves'


LoL. Yeah, whatever ADA is doing right, seems like they're not above marketing woo. Should I fill one of my filter trays with magnetic health beads?


----------



## nfrank (Jan 29, 2005)

150gallons (570L), including 30g sump. 500gph(31.5LPH) flow, guestimated from head height and pump rating.

Part of the function of a filter is to provide good water circulation. Water circulation to keep nutrients and CO2 well mixed. ADA tanks may like high flow filter pumps because they dont like to have Hydor Koralia's, powerheads or paddles in tank.

For filtration, flow rate depends on the filter materials (surface area, composition) to determine contact time and bacteria efficacy.

------
BTW, lets remember that this is an international forum... why only report numbers in gallons!


----------



## Cavan Allen (Jul 22, 2004)

niko said:


> My answers:
> 
> Now, let's be clear here - the additional flow from powerheads, fish movement, hand movements in the tank, ladles, paddles etc. do not count.
> 
> --Nikolay


I can see not mentioning ladles, but powerheads? Why not? I greatly value good water flow, and feel that it's probably OK to add additional flow creating devices (and perhaps flow patterns) to the discussion.

Mechanical filtration isn't the whole picture.


----------



## endgin33 (Jun 10, 2008)

One thing that may be of relevence to filter volume is literally how much physical mass of bacteria can be supported inside the canister. A large canister volume should be able to support a greater sized colony of all bacteria after all, right? If you could dry and weigh all of the bacteria in a 1 gallon canister filter running at 250 GPH, and then do the same to a 3 gallon canister that also ran at 250gph, for instance, won't you suspect that the 3 gallon filters total bacterial mass to be larger? Don't know if that is what Niko is getting on about, but I suspect it may be relevant. Also, the total contact time with the bacterial would be higher in the 3 gallon filter.


----------



## grak70 (Jan 5, 2010)

> Mechanical filtration isn't the whole picture.


Definitely. Powerheads help circulation in the tank, but they don't affect flow in the filter, which is why niko excluded them. Won't their effect in that regard be purely mechanical (e.g., mixing)?

The flow rate through your filter on the other hand (subject to the media you use) will affect boundary layer thickness. High flow in the filter ->turbulent->low BL thickness-> smaller diffusion length->bacteria are more effective. My theory is that it has to do with the Sherwood number in the filter. If the pores are very small (and we want them to be so our bacteria colonies can be large), then flow needs to be fast to make mass transfer easy.

http://en.wikipedia.org/wiki/Sherwood_number


----------



## Cavan Allen (Jul 22, 2004)

grak70 said:


> Definitely. Powerheads help circulation in the tank, but they don't affect flow in the filter, which is why niko excluded them. Won't their effect in that regard be purely mechanical (e.g., mixing)?


I gave my response with Neil's in mind (#7); I believe that good circulation of co2 and nutrients is more important in planted tanks than biological filtration. Hence, the inclusion of additional flow devices is of interest to me in regard to this thread. Good flow, or the lack thereof, can make a BIG difference.


----------



## nfrank (Jan 29, 2005)

grak70 said:


> If the pores are very small (and we want them to be so our bacteria colonies can be large), then flow needs to be fast to make mass transfer easy.


If the pores are small and get clogged with debris, then what type of bacteria will the available O2 support?


----------



## niko (Jan 28, 2004)

Oh, me and biological filtration go way back. Here's how I saw it until about 2 weeks ago:

http://www.aquaticplantcentral.com/...ons/66499-crystal-clear-water.html#post504948

But there's more, much more. I posted Dummy Question #007 to basically confirm a suspicion - we do not filter our tanks right. We get away with it because of many reasons but setting yourself up for failure is basically the norm.

So far only Tex Gal is getting close to what ADA suggests as flow through the filter.

Cavan,

I want to focus the attention to the flow through the filter only. Yes there are tons of bacteria in the tank itself. But maybe we can see them as "additional filtration capacity" - only after we have set up things right.

Forget ADA, I wonder what flow does Oliver Knott has in his tanks. They always look completely absolutely uber clean. But we will start to get close to information that we are really trying to avoid - old school German filtration approaches...

http://www.pbase.com/plantella/root&view=recent&row_count=20

On most of those pictures the water is simply invisible!

--Nikolay


----------



## ashappard (Jun 3, 2006)

niko said:


> But we will start to get close to information that we are really trying to avoid - old school German filtration approaches...


mattenfilters?

all but one of my tanks are unfiltered. Mainly out of laziness and desire to have as little equipment as I can get by with. Still, I do wish I had a bit of mechanical filtration to get the particles which end up settling on the substrate. My filtered tank has a moderate fishload, so I use a sponge. The sponge gets a lot of what usually ends up settling around the tank.

I got powerheads and needlewheel pumps galore though. Need that circulation for plant health.


----------



## niko (Jan 28, 2004)

Mattenfilters!

You have discovered my only secret!!!

But there is more than buying a blue sponge from Swisstropicals. Look at the 3 questions that started this thread.

ADA actually uses mattenfilters too. But not as the main filtration media in their filters.

What a mess!

Why everything has to be so complicated? Can't I just dump 50% of the water 1-2 times a week, add a few teaspoons of dry fertilizers and call it a day? I wish someone comes up something like that...

"Wait a minute..."

--Nikolay


----------



## nfrank (Jan 29, 2005)

Although i use poret sponges for mechanical and probably biological filtration (same material as mattenfilters), the water in my pictures is not invisible because i dont shut off the needle wheel pump. The micro bubbles of CO2 are great for plants but terrible for pictures. 

Not counting gilvin, invisible water can also happen without filters. I might only use a filter sock in the sump for large debris, if it didnt require frequent cleaning.


----------



## ashappard (Jun 3, 2006)

nfrank said:


> the water is my pictures is not invisible because i dont shut off the needle wheel pump. The micro bubbles of CO2 are great for plants but terrible for pictures.
> 
> ... invisible water can also happen without filters. I might only use a filter sock in the sump for large debris, if it didnt require frequent cleaning.


agreed on both points. I did notice bubble size got much smaller though after I did meshmod on my needlewheel - but still for a fancy shot, turning off the gas is best. I usually forget and take the shot anyway, and if its a macro shot I see the bubbles later as I'm going through the pics. 

I did start placing a dense sponge over my octopus venturis after stirring up the substrate. Clears the water column quicker. But then off they go after a few hours. Usually 24hrs of UV after a big substrate stir. just in case ( or superstition )


----------



## Tausendblatt (Sep 16, 2009)

I have a ten gallon tank and it has a filter rated for 20-40 gallons. I don't know the exact flow rate but it creats quite an aquatic breeze, enough to shove stems all over the place. There are some BAD things about filters: 

Exhibit A: they suck up mosses, small liverworts and Lemna Trisulca.

Exhibit B: They lower the concentration of CO2 in the water

Exhibit C: I don't know if it is good for plants or what, but seeing Ambulia bent 180 degrees is probably not very beneficial. But I could be wrong.

Exhibit D: It uses up electricity. Electricity doesn't grow on trees!!

Exhibit E: It kills baby copepods and daphnia. I had a tank that had no filter and I grew a plethora of harmless planktonic critters. Although I ended up with midge larva, nothing bad really happened. Although, AMANO doesn't say, "though shalt have zooplankton in thine tanks."

I didn't have a filter earlier in my 10 gallon, because I wanted to grow Lemna Trisulca, a small free floating submerged species. (sort of riccia like) I succeeded.
But then I got a large amount of BGA. Coincidence? I am not sure. Allegedly, BGA likes low currents and low oxygen spots. But allegedly BGA dislikes currents and high oxygenated water. Fact or fiction? I have yet to conclude. But I rinsed out all my BGA infected moss and pulled it all off the substrate. Hopefully, it doth not return. Filter free tanks are a viable option, but not with large oxygen hungry species. Tinfoil barbs and Bala sharks come to mind.

I like the dummy questions. Hey, something just occurred to me. I think that what the Japanese style does that other styles don't is use large amounts of strange mosses, use moss, rocks and foreground plants in a mix, to form an interesting carpet (rather than keeping them seperate) and perhaps emphasis on tall grasses, and a well defined midground with plenty of negative space. But just like a chef or a fisherman, many will not disclose their secrets so easily as us. But still, there are many talented aquascapers in Europe and North America (even south america and other places) but they are just a different style. Less rocks mostly.

After reading the link again, I have to bring up something: Palm net? What is that? Wouldn't such organic matter release tannins? That would make the water yellow. Interesting to think that 10% per hour is enough.


----------



## Cavan Allen (Jul 22, 2004)

niko said:


> Cavan,
> 
> I want to focus the attention to the flow through the filter only. Yes there are tons of bacteria in the tank itself. But maybe we can see them as "additional filtration capacity" - only after we have set up things right.
> 
> --Nikolay


I'm still not sure why you want to focus attention on flow through the filter and biological filtration. I myself am concerned primarily with mechanical filtration and circulation; under most circumstances, we aren't worrying about ammonia/nitrate and so on because the plants take up most, if not all of that.


----------



## DVS (Nov 20, 2005)

endgin33 said:


> One thing that may be of relevence to filter volume is literally how much physical mass of bacteria can be supported inside the canister. A large canister volume should be able to support a greater sized colony of all bacteria after all, right? If you could dry and weigh all of the bacteria in a 1 gallon canister filter running at 250 GPH, and then do the same to a 3 gallon canister that also ran at 250gph, for instance, won't you suspect that the 3 gallon filters total bacterial mass to be larger? Don't know if that is what Niko is getting on about, but I suspect it may be relevant. Also, the total contact time with the bacterial would be higher in the 3 gallon filter.


I don't think so, bacterial mass will be a factor of available nutrients, ammonia and nitrites in this case. Having a larger filter will not increase the bacterial mass. After a critical size filter volume can't have any effect on bacterial mass. Now a larger filter could reduce the incidence of bypass and clogging and therefore flow between servicing?


----------



## grak70 (Jan 5, 2010)

> After a critical size filter volume can't have any effect on bacterial mass.


Do we know what that critical size is though? Maybe we're underestimating? If we underestimate the biofiltration we need, it produces a lead-lag behavior in the tank if something spikes. If we're not at the point where decreases in available nutrient are limiting bacterial population, more is still better.



> Now a larger filter could reduce the incidence of bypass and clogging and therefore flow between servicing?


Do you think that the high flow rates (and resulting high pressure drop) ADA recommends counteract this to some extent?


----------



## Cliff Mayes (Jan 29, 2007)

Who knows what the correct amount of filtration is? I recommend at least two power filters on a tank as insurance for when one fails but, to repeat the question, what is the proper amount of filtration. We assume that the film we find on those things on the tank are from bacterial colonies and other stuff in the tank but are they really. Bacteria are tiny microscopic creatures, and there are a lot of different species (all eating and excreting something) that co-exist, who knows where. We make a lot of assumptions and listen to word of mouth but actually know very little about the bacteria other than a very gross way.

So I agree that perhaps some progress may be had by un-assuming a lot of things. As I have said many times this is a very young Hobby and is not worth much in the scheme of things. Other than a few souls trying to get rich off of some new idea or product, not much money is available for research even though there are large numbers of people who have tanks they do not get much respect.

Answers? I wish I had some.


----------



## niko (Jan 28, 2004)

Research?

Some answers that will go a long way are out there. I said it in like Dummy Question #001 or 002.

Here's what one could start with. Google for info providing you care to do it:

Say your filter happily moves the water, all nicely filtered, completely clear, void of everything but all the things that your beautiful plants need. The water coming out of the filter is being mixed with the bad, stinky water in your tank. So the filter sucks some clean water + some dirty water. Hmmm... So....

*How many times does the mixed water from the tank has to pass through the filter so all of it gets actually filtered?

A. 1 time
B. 2 times
C. 3 times
D. 9 times
E. 18 times
F. 36 times
G. I don't care. My tank is fine without your stupid questions.
*

--Nikolay


----------



## endgin33 (Jun 10, 2008)

I look at the physical size of the filter as similar to the dwell time issue in UV sterilization- Larger filter volume versus smaller filter volume at a identical flow means more time in physical contract with the filtration mechanism. (be it bio, chem or mech...) Also, we are assuming that the bacteria levels are primarily limited by the nutrient levels in the water (ammonia, etc) that we can "feed" them- however I am not necessarily convinced that "food" is the only important limiting factor in this instance. Over-population studies with rats show some crazy cycles if you give them lots of food in tight quarters. just a thought


----------



## Diana K (Dec 20, 2007)

"*How many times does the mixed water from the tank has to pass through the filter so all of it gets actually filtered?*"

http://www.seachem.com/Library/Articles.html#FiltrationPrimer
Read A Primer on Aquarium Filtration.

Along about the last half of the article has tested numbers for flow rate through various media, and what is the optimum flow rate to remove debris from the water. How much is knocked loose after it is trapped the first time, and how many trips through the filter that debris has to make before it is trapped for good.

Turns out the thicker the mass of media the better. 
A larger the face area the more the force of the water is spread out, so it does not knock off debris that has been trapped. Think of a canister made out of 6" PVC pipe: Thick mass is good, but the water still flows through pretty fast. Debris gets knocked off, but the thick stack may trap it again. Now figure the same volume of media, but put it in a 12" diameter pipe. The pipe is shorter, but the force of the water is less in each square inch, so less debris is knocked loose. Now make it bigger again. Maybe a single sheet of sponge, (same volume of media) but perhaps a 24" diameter pipe. Not so good: debris might pass through the thinner stack of media and not get trapped at all.

As for the first Q:
I tend to set up my tanks with a filter (or more than one) rated at 10 times the tank volume per hour. Whether I am actually getting that is debatable. I think some of the manufacturers measure the flow rate with an empty filter, or other tricks that make their info questionable, and certainly as the filters fill with debris they slow down. 
I add power heads with a sponge over the intake that in theory would increase the water movement to 15-20 times the tank volume, but again, I have serious doubts about the accuracy of the labels.


----------



## niko (Jan 28, 2004)

Ok here's something else:

http://www.pbase.com/plantella/lme2

That tank has no CO2, it has very low light and plants that feed from the substrate. Fish are quite a bit. Filtration as you see is not per ADA - the 2 Eheims under this 240 gal. tank move no more than 800 gals. of water (if we forget that there is a hydrostatic head). In my opinion it's more like 600

But look at the tank! I bet each one of us can make the same clean, low maintenance tank because we know it all. Right?

Funny thing you can read Oliver's comments about each tank in that endless gallery but you can never find the actual maintenance described.

My point is - it's very obvious there are things to be learned.

--Nikolay


----------



## Cliff Mayes (Jan 29, 2007)

You are quite right. Dwell time of any given chemical is probably a factor. While it is true that Chemical and Mechanical filtration are important and probably measurable biological filtration is not as easy. Bacteria as I said are very small and how are we to measure them? Flow is an important aspect of our tanks but how do we know whats right or enough. Not too much or too little. Here I am asking questions instead of providing answers, but after many years of ups and downs all I have left are a lot of questions.

There are very few, if any, trustworthy scientific measures about the Hobby. Even so called scientific results are suspect and subject to review. Evidence gleaned by Hobbyists empirically is not to be discounted even though information must be filtered through many people over a period of time.

Manufacturers not being truthful? What a revolutionary thought. Everybody wants to get rich so it comes as no surprise that the "truth" gets bent or warped out of shape. Maybe an important question is "who can you trust?"


----------



## niko (Jan 28, 2004)

Diana K said:


> "*How many times does the mixed water from the tank has to pass through the filter so all of it gets actually filtered?*"
> 
> ...I tend to set up my tanks with a filter (or more than one) rated at 10 times the tank volume per hour. ...


So tell us that your tanks are completely algae free. I'd like to find closure to all this.

Or else I will say it again - an aquarium is a system, we have been failing at seeing it as such, it's about time we get some useful information. Ourselves.

--Nikolay


----------



## MoonFish (Feb 12, 2006)

Niko, I got a kick out of your other thread. I was browsing a bit and came up with this discussion of the filters 
http://www.aquaticplantcentral.com/...gn-group/6674-where-can-i-find-more-info.html


> "With this classical style of external filters, we employed a new system
> of water activation which Plocher Vertriebs established in Germany.
> The form of the filter cannister is designed for effective circulation of
> water through the filter media which minimizes the burden on the motor
> ...


I think "minimizes the burden on the motor" means there is blowby or recirculation in the filter. I would kill for one of those pumps btw. The more fine sponge/media you have, the more flow you lose. Maybe they can run a lot more of that and that leads to another idea.

I'd say the flow recommendation is very specific to make a tank that can have all inline stuff and still have a lot of water movement so every plant isn't pearling all the time because that isn't photo friendly. Most of use would agree a standard sized canister is not sufficient flow, it won't collect all of the dead plant matter or keep a nice carpet like the showboat tanks have, clean. Of course we would all want more if money wasn't a barrier. Powerheads are cheap and I'm [email protected]

Bigger size just lets you go farther between maintenance. $ vs time. Stability too.


----------



## houseofcards (Feb 16, 2005)

I'm very curious to see where all this is going. I hope I'll be pleasantly surprised. I'm not sure I get the filter flow thing since so many factors would determine how big of a filter one would need (maintenance schedule, fish load, lighting, type of setup, feeding, etc.) I'm sure a bigger filter can't hurt in most situations, but once the tank get's established isn't most of the filtration in the tank and the filter itself secondary. Look at saltwater, isn't the primary filtration live rock. 

I'm not sure what the Knott tank proves. It has about 0.5 wpg and water changes weekly, it doesn't sound that difficult to keep clean. 

Again I'm sure a larger filter is great, but certainly not a necessity depending on tank parameters. You are giving me the impression that a true ADA tank with all the bells and whistles never gets any algae throughout it's lifecycle. I love the ADA stuff, but Amano clearly states how to deal with algae during the startup and how to deal with it when the tank ages, which by the way he states that algae is enviable in every tank eventually. I'm all for new information, but lifestyle and discipline factor into this as well as the science. 

BTW - My big tank (72G) has been up for a year. I run a Eheim 2215 (160gph) and the actual effective turnover is probably slightly more than 1 time per hour. I also run 3.5wpg on it and the tank is extremely clean. All I do is change the water weekly and keep my filter clean, feed my fish once a day, 6 days a week. I would show a pic, but I've bloviated enough.


----------



## grak70 (Jan 5, 2010)

It may be helpful for the sake of argument to consider the extremes. What happens if you have no filter and just agitation? What happens if you have an infinitely large filter? What are the consequences (not just on tank chemistry) of these two scenarios?


----------



## niko (Jan 28, 2004)

House,

The purpose of the Dummy Questions is to make us more aware of factors that we don't normally consider. Since there are so many variables it's a good idea to at least have some idea about them. These are the first steps toward better understanding what happens in planted tanks. And from there - to better handle the issues.

Some people have figured it out already - Amano, Knott for example. We in the US as a whole have not. Our best bets are EI and PPS. And of course our own personal way of doing things which, as always, is superior to everything else.

Grak,

A planted tank without a filter:
Runs fine. If the maintenance is consistent, the fish load is light, the plants are abundant you can have a tank with only water movement. Adding a filter to such a tank actualy slows down the plant growth a little bit. But if you hook up a filter you will see a difference in the plant growth.

It's a fine ballance so the wellbeing of such a tank is rather fragile. I always said that in a properly setup planted tank the filter is just a buffer in case anything happens. But overall it's better to have a buffer than not to.

A planted tank with a huge filter:
That's what we need to be doing actually. The argument that the bacteria will eat the plant's food before they got out of bed is not really an argument. Plants prefer NH4 and there is always some of it available no matter how big and active the filter is. You cannot remove all the NH4 that forms in a glass box and kill the plants by starvation. They slow down their growth considerably but will not die. 

Such a tank will be able to handle pretty much every issue by itself. I don't think you will ever even notice issues with it. Overall - the companies that sell filtratoin equipment should provide more information. But do they really want to?

--Nikolay


----------



## niko (Jan 28, 2004)

Diana,

I read the Seachem pdf and all I can say is I wish there was more information like that available. The pdf talks about important things but it doesn't give any specific suggestions on how to setup your filtration. I have to read the document again though. I didn't read it very carefully last night.

Also - I don't know if the posts after yours were influenced by that pdf file, but I think that linking to it just shows how little interest actual information creates. Maybe it's the nature of the information itself but I didn't see any explosion in the discussion after you posted the link. Maybe now someone will start to understand why I'm doing the Dummy Questions in such a mocking and frustrating manner.

--Nikolay


----------



## grak70 (Jan 5, 2010)

So from the Seachem article, it appears activated carbon is not as useless as some people have said. And it addresses the dissolved organics problem alluded to in the COD discussion...hmmm.


----------



## nfrank (Jan 29, 2005)

Nice presentation and linked article by Steve Rybicki PRESENTATION 
suggesting that high flow can be bad if it causes particles and heterotropic bacteria to be dislodged and flow back into the tank. So, high flow means cleaning more frequently. Steve also mentions concerns about heterotropic bateria: "dissolved organics and heterotrophic bacteria would destroy the fins or kill the fish long before ammonia or nitrites became a problem." In addition, he points out that "filter [should] not clog so the nitrifying bacteria has constant exposure to oxygenated water." Since his presentation was not oriented towards planted aquaria, he does not discuss the advantages of high flow to distribute CO2 and nutrients.

Here is a more scientific treatment of the subject Bacteria and nutrients-nitrogen and carbon-in a recirculating system for sea bass production . I have not yet read the article. The author concludes that "What appears to be vital is the quantity of feces reaching the biological filter, which can be reduced by a good mechanical filtration and a good feed conversion index."

Another source of info to peruse is http://www.dataguru.org/misc/aquarium/waterinfo.html


----------



## lildark185 (Jul 7, 2006)

niko said:


> So why would ADA suggest such humongous flow rates? And such monster sized filters?
> --Nikolay


They want the largest possible filter so that there can be the largest amount of beneficial bacteria. This coupled with humongous flow rates would increase water turnover much quicker so that the bacteria can polish the water constantly resulting in "invisible" water.


----------



## Shad0w (Nov 13, 2006)

I was thought that it is to provide plants with nutrient (Soluble CO2, N, P, K, trace, etc). Since many of ADA scapes are full of plants, its need bigger filter flowrate to reach all part of the tank because plants will block some of the flow


----------



## DVS (Nov 20, 2005)

lildark185 said:


> They want the largest possible filter so that there can be the largest amount of beneficial bacteria.


Even regular size filters provide more than adequate surface area for beneficial bacteria. These bacteria are limited by nutrient availability. Bacteria of any kind will reproduce until the point where the population is stable based on "food" availablility. If area were limiting bacterial population it would be evident due to fluctuating levels of ammonias and nitrites. Since neither of these is evident in a mature tank (even unplanted) we can surmise that even a standard filter provides adequate area. And before somebody brings it up, bacteria do not practice family planning waiting for one of those flashy ADA pads (filters) to be provided . Bacteria reproduce until their population is in balance with their food source.

High Flow and a big filter provide 3 advantages as far as I can see.

1.) Better mechanical filtration- Deeper beds, and less clogging due to available area.

2.) Better chemical filtration-for same reasons better mechanical filtration is provided.

3.)Higher sustained flow rate between servicing. Again based on geometry of larger container.


----------



## niko (Jan 28, 2004)

It appearst to me that high or low flow you can have a clean tank either way. Depends on the history of the tank. We talked about organics in some of the Dummy Questions and it appears that if you allow organics to accumulate it's very hard to get rid of both the organics as particles and of the results of their accumulation. If you never let organics accumulate you will be way ahead in this game. Filtraton and filtration maintenance are the 2 somewhat important things to many of us. That should be the usual answer route to the common question "How do I get rid of my algae?". But please don't just advice "Yeah, clean your filter an see what happens..." There is more to that.

ADA suggests high flow (8-10 times the volume if the tank per hour). But they do not use any special secret material in their canisters. Actually the material is not very porous either. Every single aquarium merchant will try to convince you that the smaller the pores of the filter media the better because there is more surface for the bacteria to live on. That's not so. Or rather it is so depending on other parameters of the tank. It's like trying to sell gramma an 18-wheeler truck because "it holds a lot of groceries" - maybe gramma is a tatooed truck driver, maybe she's just a truck driver. Or maybe she's pretending to know trucks so you don't try to sell her a lemon. And really the best fit for her is a compact car.










In all this what are *the things that we positively can not deny*?

*A.* Basically if you have a lot of surface area with a lot of flow over the biomedia it's logical to assume that you will have superior filtration. But how much area is too much? Apparently it doesn't make much sense to have a 55 gal. tank and a filter that is 55 galons too. There are answers out there to these questions. Once again I'll let you down and instead of spilling the beans I'll urge you to look for them.

*B.* The flow rate over the media could be viewed as a way to supply Oxygen. The more flow you have the better in that case. But of course too strong of a flow and you will be blowing the bacteria away. So here we could start to see the dependency between the media's surface area, the porosity, and the flow.

*C.* Of course in most cases we'd like to have the filter attached to a tank. So whatever happens in the tank also affects the equation "media + porosity + flow". It's easy to agree that a tank with 1 small fish should be able to do fine with less media, less porosity, less flow through the media. So one could conclude that the size of the tank, its inhabitants, and the maintenance schedule become part of the factors influencing the filtration. That's nothing new of course. But ADA seem to have put together all of these things and if you follow their approach you will be better off than just adjusting things yourself. That's not to say that you can't - that "guessing game" is part of the enjoyment of the hobby.

*D.* One parameter that hugely affects the filtration and we, once again, do not pay much attention to is the flow inside the tank. Look at ADA's funky glass intake. The thing looks like it has been designed by a high end designer and has no other purpose than to suck water while looking pretty. Yes, but no. The positioning of the intake, the notches on it, the fact that it doesn't have an opening on the bottom - these are all little things that to us seem unimportant. More information here - www.google.com. Oh, yes, and the intake works in conjuction with the outtake - the Lily Pipe. How mesmerizing!










To someone that still thinks I'm an ADA-and-nothing-else proponent I have to say you are right and you are wrong. As we said before - ADA has not really invented anything new. But has gathered and packaged it in the best system ever. No matter what we find to work fine we can be pretty much sure they are doing it already in some way as part of their system. Catch 22 in Japanese:










--Nikolay


----------



## houseofcards (Feb 16, 2005)

I have no doubt that a bigger filter can only help, but as you pointed out with "Grandma and the 18 wheeler", there's a difference between better and practical.

I personally think in most cases the role of a filter for 'biological' filtration is very over-rated. For me a lot of things you mentioned in your last post ring true. When the tank is first set-up the filter is the primary 'cleansing' system. There isn't much going on in terms of biological filtration between the media and the plants. That's why it's always beneficial to load the filter with carbon, purigen (or other organic removal) and mechanical. This will prevent the buildup of organics which is why so many people have issues at startup. Once the organic load get's going there is no biological filtration to deal with it so we are relying on the chemical and mechanical to fill the void. Then the switch, once the tank matures and the plants are growing and the substrate matures the filter to me is just a secondary 'cleansing' system. Other than flow most of the filtering is done in the tank. Which is usually when you go through that stability phase. The larger the tank the less the filter has on the overall cleaning. As the tank ages, regardless of filtering capacity there is an eventual build-up of organics, whether it be in the substrate, filter or both that leads to problems. How well you maintain the filter, and do regular water changes, etc. will dictate how long the tank stays algae free.

Here is an interview conducted right here on APC with Mr. Knott several years ago.

http://www.aquaticplantcentral.com/forumapc/aquascaping/82-weekly-topic-interview-oliver-knott.html

I found this exchange in the interview very interesting:

*Carlos: Finally, is there any particular advice you would give to a hobbyist creating his first planted aquarium layout?

Oliver: Consistency is the most important, I think. Water changes, fertilizing, cleaning, pruning the plants --all these jobs should be done regularly.*

The key word being 'regularly.' I don't think this is anything eye opening and I think many seasoned folks here do the same thing. His response to me speaks discipline, lifestyle not science.


----------



## nfrank (Jan 29, 2005)

> Here is an interview conducted right here on APC with Mr. Knott several years ago.
> 
> http://www.aquaticplantcentral.com/f...ver-knott.html


Thanks for posting this link. Although off the "007" topic, whatever possessed so many "american" aquarists in using so much light. I think my brightest tanks ever are my current ones, and i only run them full strenght for part of the day. I never had one with more than 2.5wpg (although that is clearly not the correct metric). See the KRIB's lighting survey Survey and various 1998 Comments. You may find them illuminating! And I am sure the role of light intensity will come up as a forthcoming "dummy" question.


----------



## Natalia (Sep 15, 2008)

Niko,
I am now courious about the intake. Do you think the purpose of this peculiar design is to have the debris suspended in the watercolumn? This way it will get sucked into the filter without hitting the substrate? The lily pipe is to create a surface agitation to help gas exchange? Just a guess on my part...


----------



## Diana K (Dec 20, 2007)

"So tell us that your tanks are completely algae free. I'd like to find closure to all this"

Absolutely not! I seem to have a different species of algae in each tank!

Not going to find closure from me! I like research that is done sitting at the computer, but to actually get up and do something sounds like too much work.


----------



## Reginald2 (Feb 8, 2009)

Diana K said:


> Not going to find closure from me! I like research that is done sitting at the computer, but to actually get up and do something sounds like too much work.


I have to bloviate, and you all know that... but lol.


----------



## Shad0w (Nov 13, 2006)

I do not think there is such thing as completely algae free tanks. Unless the tank is empty


----------



## tiffc (Jan 8, 2010)

I just read the interview with Oliver Knott, and I'm glad it was posted! I always wondered if there were any well-known aquascapers that specialized in low light tanks! 

Any others that I should know about?


----------



## niko (Jan 28, 2004)

tiffc said:


> ... I always wondered if there were any well-known aquascapers that specialized in low light tanks!
> 
> Any others that I should know about?


Amano for one. Or is he?

Well, it seems to me that it's about time we start Dummy Questioning the light in a planted tank.

So here it is - look for Dummy Question #008. I will not post a link to it here. Hard work to find it I know.

--Nikolay


----------



## lanceduffy (Jul 15, 2010)

Niko,
Thanks a lot for the dummy series. The link on the post that has started Question #007 is broken. I am really trying to figure out what the magical red text says. 

I have been following your thoughts on filtration and have found that increasing the flow through my filter has been helpfull in keeping my water clear and, people can debate the cause, but I have very little trouble with algae. I don't even use excel (gasp)! 

In some of the other filter threads you have discussed 10x tank volume per hour as a good rate of flow through the filter. I am wondering if that is what the magical red text refers to?

What has confused me, is that when I look at the data that Amano provides on his tanks, unless my math is wrong, his turnover rate is 3.15x/hr on the large tanks (180x60x60 with an ES 2400) and 6.8x/hr on the 90x45x45 ES 1200.

Please sir, the red text?


----------



## JustLikeAPill (Oct 9, 2006)

Amano uses a turnover rate of approx. 5x on 60-p's with the ES-600

Amano doesn't really use high turnover on his tanks it seems. Mosty low to medium. It seems that 10x turnover rate isn't really necessary. We should be aiming for 5x of actual turnover rate. Most commonly available filters run at half of the stated flow on the box, so aiming for 10X is a good idea because you will likely only get 5X. 

Even on eheims, the flow is much slower than what the box says. 

Of course that is all assuming that Amano's method is ideal.


----------



## niko (Jan 28, 2004)

I have forgotten already in which thread we talked about that. I think it was a year later, after this thread, in another thread about filtration and flow.

Basically what became pretty obvious (if you looked for it in all ADA tanks) was that the idea of a "good" flow rate depends on:

- What you use as a filtration media
Does it clog easy or not

- How you place the filter intake and outtake
The idea is to create circular motion in the tank - from outtake to intake. Without any pumps confusing that flow.

- How close to laminar you get the flow to be
It appears that laminar flow "pulls" water from all areas of the tank and involves it in the main circular pattern of movement. Strong flow coming from a jet is about as far from laminar as you can get. 

- Use of properly designed Lily pipe
It has a peculiar characteristic - it increases the flow rate by involving water from the sides of the main outflow area.

- How dense are the plants.
Plants block flow badly. Very badly. An iwagumi will need much less flow than a Dutch tank.

- Are the plant gently waving in the current
If they are not - increase the flow.

Over the last year there were a few actual accounts that the above things actually work. I was far from hoping that everybody will stop whatever they are doing and start increasing flow and adjusting flow patterns. People like to discuss fertilization as a cause/cure for everything and to discuss algae I guess. But the above things make a lot of sense.

The 10x the tank volume flow requirement comes from the fact that the water needs to go through the filter 9 times until it's filtered 100%. That is taken from some scientific text. If I'm not missing something apparently it is not the same text that says that the filter needs to be 10% of the tank volume. So I don't quite understand why you need to run the water 9 times through your filter if there is no reference to the filter size. Anyway - if one does not agree that our filters are normally undersized then this discussion is pointless. I believe we need larger filters and more flow, that's it. Proper setup of a pond requires filters that are 50% of the pond volume - that's a fun fact, allright. So for one's home aquarum the questions of how much flow, how exactly to setup everything, etc - need to be answered based on what you consider common sense. Exact numbers are just good reference points.

--Nikolay


----------



## JustLikeAPill (Oct 9, 2006)

Amano seems to think filtering about half of the water per hour is sufficient. Even in tanks full of plants and wood.


----------



## niko (Jan 28, 2004)

Am I reading this right? 

So on a 180 gallon tank he would put a 90 gph filter?


----------



## lanceduffy (Jul 15, 2010)

Thank you for the clarification. Very helpful.


----------



## lanceduffy (Jul 15, 2010)

Niko,
Something is strange with this forum software. My last post was in response to your post #50.
I am not confident in my math. But the information I used to get the numbers I arrived at was from here: 
http://www.aquajournal.net/suikei_data/index.html 
The links on the left provide you with data on the tanks including size of the glass cage and filter type.
I just looked up the specs on the filters and tank sizes on ADA's site. Remember the filters are spec'd in liters per minute and their tanks are sized in liters too. 
To get my turnover rates for the data ADA provided, I multiplied the liters per minute output of the filter by 60 to get liters per hour. Then I divided the liters per hour of the filter by the capacity of the tank. = turnover rate right?
I'm sure there is more than one way to get to this number. My head hurts. Someone help!


----------



## JustLikeAPill (Oct 9, 2006)

No, but if I attempted to duplicate Amano's method, I would use a 900 gph filter. 

Actually Amano would likely use one ES-2400 on a tank that size (427 gallons per hour)


Me, PERSONALLY, I would use two filters on the same side of the tank rated at 500 gph. And I wouldn't use Fluval FX5's... I'd use the big Eheims! 

Lanceduffy, your math is correct. Be sure to use the smaller number listed on the filters because that is their rating in Japan. In America they push more water.


----------



## lanceduffy (Jul 15, 2010)

Thanks and call me Chris.

I am aware of the 50hz vs. 60hz and the output difference. As you saw, I did my calculations at 60hz output.


----------



## OTPT (Sep 27, 2010)

lanceduffy said:


> Niko,
> Something is strange with this forum software. My last post was in response to your post #50.
> I am not confident in my math. But the information I used to get the numbers I arrived at was from here:
> http://www.aquajournal.net/suikei_data/index.html
> ...


Amano has written an article for TFH magazine about filtration in the Nature Aquarium.
http://www.tfhmagazine.com/details/articles/filtration-in-the-nature-aquarium.htm

In the article he notes that too strong flow will uproot and sway the plants, and limit 
the choice of layout.

He gives his preference about tank sizes vs flow rate as well. 
And mostly they're quite much lower than 10x. I think the average is around 3-4x.


----------



## jeff5614 (Feb 15, 2006)

Great link. Thanks.


----------



## niko (Jan 28, 2004)

This topic was written some time ago when I was trying to understand what is it about the setup and maintenance that the Japanese do that makes their tanks different from the tank of the average US hobbyist. I think that I have an understanding now. The difference is like night and day. Seriously.

As for the flow - the flow rate depends on the layout.

And there are 3 more points:

- *Main point:* The way the Japanese run their planted tanks is very different from the way the average US hobbyist runs their tank. We overlook many parts of the system and work against them. Because of that copying the Japanese without understanding why they do something is not a good idea.

- The flow pattern makes a huge difference. There is enough information on the internet about that now, including at least one very detailed topic here on APC.

- Try to filter a 150 gph tank with the 480 gph that Amano suggests. You will see that it's not a good idea.

The TFH article is written in the typical generic style. There are good reasons for that.

--Nikolay


----------

