# Walstad-Method Tank: Questions



## gravy9

Hello everyone,

I'm new to the Planted Aquarium hobby. Got into it by accident when my wife and I got our 7-year old daughter a fish tank. I read a lot before getting the tank and hence purchased a 38-gallon tank to minimize the parameter fluctuations. Once we got the tank, I maintained a log until the completion of the cycling process, testing every other day for Ammonia, Nitrites, Nitrates and pH. This was a great learning experience for me and my daughter started learning everything about the fishes in the tank.

All the reading got me interested in creating a self-contained ecology within the tank, with the fish feeding the plants and vice versa. The more I read, the more interested I became which was when I stumbled into the books by Diana Walstad and Christel Kasselmann. I absolutely loved the two books. One area I constantly struggle is the aquascaping layouts and decided that I'll keep trying until I get it right (at least in my mind).

Currently, I'm in the phase of experimenting with different types of substrates and trying to document the pros and the cons just to learn more on the substrates. I have a 12-G tank that has only Flourite in it and a few plants along with the small Eheim Aquaball filter (not the powerhead). I'm also planning on building another 20-G Long using the Mineralized Substrate based on Aaron's article sometime in October.

That said, I purchased a few smaller tanks from Craigslist (all the expenses were out of my pocket money as my wife said that she will not be funding these expenses out of the common account -  - if not for her I'd have been bankrupt a long time ago ). Anyway, I have a 10-g that just has some Java moss and some Riccia growing. I setup a 20-G Long using the Diana Walstad method (DW henceforth) with the specifications shown below.

*Walstad-Method Tank*

Tank: 20 Gallon Long Glass Aquarium
Fish: None yet
Substrate: 1 1/2 inches of Potting Soil + 1 inch of 1 mm size Sand
Amendments: Sprinkle of laterite + 1 handful of Peat
Filter: None. But using Eheim Aquaball powerhead for water movement
CO2: DIY Yeast-based CO2 generator fed to the powerhead air intake
Lighting: 4x GE Aqua Rays 4100K 24" 20W T8 Bulbs and Filtered Sunlight (South facing window)
Lighting Fixture: 2x Utilitech 2-Light Narrow Fluorescent Wraparound Light (http://www.lowes.com/lowes/lkn?action=productDetail&productId=80803-13537-80803&lpage=none)​
Here are my questions:
1. The tank started turning murky right from the beginning. I'm guessing that this is due to the leeching nutrients. Am I right?
2. During the first two weeks, I saw a semi-transparent jelly-like substance in the bottom of the tank (mostly by the roots). What is this?
3. The Nitrate levels were very high and I performed a 75% water change. Was this right for me to do this or should I have left it alone?
4. After 2 weeks, the tank started developing a lot of green algae (long strands of bright green algae). I was able to remove this by hand. What causes this and is there a way to control it? Is this bad for the plants?
5. After 4 weeks (yesterday), I trimmed all the plants and changed 75% of the water to remove the cloudiness. Was this right for me to do or should I have left it alone?
6. I also noticed a 1-inch 1/16th of an inch wide eel-like creature that I took out the tank and flushed. I also noticed a 1/4 inch creature looking like a fry but how can one be there when I've never had a fish in the tank? Does anyone know what these are?
7. After I refilled the water, I noticed that all the Glosso in the tank had some kind of gel-type of substance near the base of the plant. What is this?
8. Fishes: When can I start putting fish in this tank and what types should I start with? Can I add otos, cherry shrimp and Amano shrimp to this tank?

If anyone has any additional suggestions or critiques, please post them.

Thanks for reading and thanks in advance for your comments.

regards,
Ravi


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## mommyeireanne

You may have problems from the peat with the soil. The high tech guys who don't use soil only dust peat on the bottom, and it needs to be Canadian Peat specifically. But with the soil, it makes a bacterial bloom as it rots. (likely your jelly and gels)
Also, layerite isn't needed with soil substrate. It can be too much iron. I got algae using EcoCompolete as a topper (because I already had it). I think it contributed. Too much iron can also be bad for plants and animals. 
You are way high on the light. Usually 2-3 watts per gallon for a NPT. You may need a little higher if you want to add CO2. But I think all the light is a big factor in your algae. If the plants aren't doing well they can't starve it off. 
It's hard to assimilate what goes with high tech planted tanks and what should be with low-tech NPTs. Those ADA tanks sure are tempting. Some people conservatively mix in one or two elements. 
You were right to change water for nitrates. Could the soil have had fertilizer in it? You'll want to have no ammonia or nitrates for the fish. The creatures likely came in as eggs on the plants. Most are grown outside. Some are carnivorous and could eat small fish/fry. If they are small enough to be eaten by fish and your parameters are ok for fish, they might be a bonus. GL.


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## gravy9

Thank you very much for your response, MEA. 

SOIL: Scotts Premium Garden Soil. The soil does have fertilizer in it. It has Nitrogen, Phosphate and Potassium.

PEAT: Thank you for your comments. This helps a lot. I used it to reduce the pH to enhance the water conditions for the tetras that I plan to use in the tank. I do not have any fish in the tank. Will stay away from peat moving forward. I think the coloration explains the effect of peat also. When I change the water, it starts turning yellowish after 2 or 3 days.

LATERITE: I added it based on my reading on the Mineralized substrate method. I just added a few sprinkles, probably around 2 teaspoons. The plants seem to be growing extremely well, except for the 2 Swords which seem to be stagnant. They're not dying either.

LIGHT: I will reduce the light to just 1 fixture (2x 20 watts) from 2. Should I just stop the CO2 supplement in this tank? Also, if I do that, would there be an effect on the algae?

FISH: I still have not added any to the tank yet. I will once the parameters stabilize.

Next time around, should I just use top soil?

Thank you again for your comments and tips. 

regards,
Ravi


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## mommyeireanne

gravy9, Definitely just topsoil next time. I don't know if you'll be able to resolve the nitrates if it's coming from fertilizer. Ditto with the algae. I guess you can wait it out and see if the plants seem ok. You're right to wait and see for the fish. Maybe someone else can give you an idea what to expect with the fertilized soil. If you decide to redo, check out this neat summery by Data Guru. If you can get your hands on D Walstad's book that would help most. Best wishes


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## gravy9

Thank you very much, MEA.

Will wait for another 2 weeks to observe and will probably redo the tank should this continue.

As for Ms. Walstad's book, I have it and ready. Thought I'd experiment and am really experiencing the after-effects of experimenting.

Thank you again.

regards,
Ravi


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## dwalstad

gravy9 said:


> Thank you very much, MEA.
> 
> Will wait for another 2 weeks to observe and will probably redo the tank should this continue.
> 
> As for Ms. Walstad's book, I have it and ready. Thought I'd experiment and am really experiencing the after-effects of experimenting.
> 
> Thank you again.
> 
> regards,
> Ravi


No matter what soil you use, it will cause problems the first two months after it is submerged ('Chaos in Freshly Submerged Terrestrial Soils', my book, pp 130-135). No soil is perfect. Be prepared to change water, maintain sufficient aeration, and add charcoal to the filter.

If your soil is richer (more nutrients), you will need to do more water changes and be more vigilant. However, that doesn't mean that a rich soil is bad or needs to be replaced. You just may need to do more water changes the first few weeks.

Once the soil is established and your plants are growing, you can relax on water changes and everything else.

I'm encouraged by the fact that you say that your plants are growing well. If they are doing well, then the soil is good and your lighting is sufficient.


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## gravy9

Thank you very much for your response Diana.

The plants have been doing extremely well and are constantly pearling. I also see bubbles coming out of the gravel continuously. However, I do not have a filter. I just have a submersible powerhead for water movement and feeding DIY CO2 while maintaining minimal surface agitation. _Should I think about adding a filter for the tank?_

I trimmed the plants over the weekend before changing the water and ever since I "think" that I'm seeing a slowdown in the formation of green algae. I still do see some thread algae but not at the same level that I saw before. Hopefully, it's starting to stabilize now. Since Sunday, the only thing that I see is that the color has turned yellow slightly. Seems very promising and hence my comment on waiting for another 2 weeks before I redo the tank.

I still do not have any fish in the tank. Am planning on adding once the parameters stabilize.

All that said, this experience since I got into planted tanks over the past 3 months have been an unforgettable experience. I'm loving it and I have been reading like never before. 

Thank you again.

regards,
Ravi


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## mommyeireanne

Yeah, Some good news! I was worried for you. Please let us know how it turns out.
M


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## gravy9

Absolutely, MEA.

Thank you very much. For sure, I will post in the next two weeks as to how things turn out.

I just noticed that the algae seem to be on the decline. Three things changed over the past week: An addition week's time, trimming of plants and 75% water change. I'm thinking it is due to the fact that I've crossed the 5 week mark since the tank was setup.

I reread the section "Chaos in Freshly Submerged Terrestrial Soils" and it starts to make sense.

Thank you again for all the help. I'm really glad that I'm part of this APC family.

regards,
Ravi


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## dwalstad

gravy9 said:


> I just have a submersible powerhead for water movement and feeding DIY CO2 while maintaining minimal surface agitation. _Should I think about adding a filter for the tank?_


In this situation, I don't think you need a filter. You've got water movement to keep the water safely oxygenated. The NPT itself functions as a biofilter (bacteria in the soil and on plant surfaces reduce ammonia and nitrite levels).

Good luck!


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## gravy9

Thank you very much, Diana. Appreciate all the guidance.

At what point in time should I think about stopping the water changes? Should it be when the Nitrates are under control?

regards,
Ravi


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## gravy9

Folks,

When changing the water today, I noticed that all the dusting in the leaves (not sure what type of algae they were) and the green algae were all gone. just a tiny bit of thread algae in the tips of some leaves. What happened? I love it now. 

The temperature of the water dropped over past week also as it's getting colder in the Chicago area. The water temperature dropped from 76 to 70 degrees. I do not have a water heater in the tank. Could this have had any influence?

Thank you.

regards,
Ravi


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## dwalstad

gravy9 said:


> Folks,
> 
> When changing the water today, I noticed that all the dusting in the leaves (not sure what type of algae they were) and the green algae were all gone. just a tiny bit of thread algae in the tips of some leaves. What happened? I love it now.
> 
> The temperature of the water dropped over past week also as it's getting colder in the Chicago area. The water temperature dropped from 76 to 70 degrees. I do not have a water heater in the tank. Could this have had any influence?
> 
> Thank you.
> 
> regards,
> Ravi


Nitrates (less than 10 ppm in aquariums) aren't that important, but temperature certainly is. Many tropical aquarium plants won't do well at 70 degrees. Why not a water heater?


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## gravy9

Thank you for your guidance, Diana. I will certainly get a heater for the tank. Is there a minimum that I should use as a reference that I should not go below for an NPT?

regards,
Ravi


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## dwalstad

"The tank has now gone with 25% water changes so far and am planning to do a 50% water change this weekend. After that I'm planning on letting it go for a couple of months without water changes. Your thoughts on this please.

Over the past two weeks, I've started seeing slowed growth and yellowing of the leaves. This is consistent with all the plants in the tank except for the Swords. They seem to be OK. Not sure what is causing this. I still do not have fish in the tank and nor am I fertilizing the tank. The only thing that's going is the DIY CO2 generator. Any guidance or thoughts on this?

Thank you very much for your guidance."

regards,
Ravi

Dear Ravi,

Since this tank has been set up since Sept, I think you could probably go several months without water changes.

I see that you've added artificial CO2 injection. This gives plants plenty of carbon so that they quickly run out of other nutrients like nitrogen, iron, etc. It is not surprising that they're starting to turn yellow indicating nutrient deficiencies. Please don't complicate this mistake by adding fertilitzers. The solution is to stop the CO2 injection, add fish to the tank, and start feeding the fish. (This will start adding the nutrients into your tank.) I don't know why you've held back on the fish. I routinely add them the next day after setting up a tank.

Remember that if you have CO2 injection, you throw the whole ecosystem out of whack. Many of your plants may collapse, now that don't have their "CO2 candy" readily available. 

I think you are worrying unnecessarily about water changes, soil, nitrates, etc. Your first NPT isn't a life-or-death issue. If it works fine, great. If it doesn't, you will learn something and then can always start over. 

You can always go the high-tech route with CO2 injection, fertilizers, etc. Right now, you're doing it half-way and inducing nutrient deficiencies in your plants. 

I recommend that people try to follow the guidelines in my book if they want to set up NPTs.


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## gravy9

Thank you, Diana, for your response.

As for not adding the fishes initially, it was just my initial fear of leeching nutrients and how it may affect them.

I'll remove the CO2 injection and if I remove the CO2 injection, are there any specific steps that I need to take to the loss of Carbon to address the short-term impact? I just added a few Red Cherry Shrimp yesterday. I will test the water and start adding the fish now.

I have a 20 gallon long. Is there any particular number of fish that I should start adding initially? How many can I start with and what should be the limit for this tank?

The conditions in the tank has stabilized and I will stop changing the water. Also, should I check anything specific during this process? 

Thank you very much for your guidance, Diana.

regards,
Ravi


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## Alex123

gravy9 as Diana said the CO2 injection is what causing the deficiencies in other nutrient(or need for more nutrient) so removing it is removing a problem not creating a problem. There will be no impact short-term. To create other nutrients for the plant she suggest you add fishes and feed them liberally. That's to help replenish the missing nutrients. You currently providing too much of one growth factor Carbon but not the other growth factor the nutrients and thus creating a limiting growth factor and so the plants are yellowing. In your original comment you said you wanted a "self-contained ecology." Without fishes(live creatures) and fish food you are missing half of the self-contained part of the ecology. As for the fish load I would add half the planned load for now. So using the rule of thumb, I would put in 10 one inch community fishes or what 10 inches worth of fishes. As for checking process, I would not worry too much. After adding the fishes check the nitrate/ammonia level every few days for a week if all is well, I don't check anymore. After 1st week, I look for signs such as uncontrolled algae growth or fish behavior, if it's abnormal or out of control change the water else do water change every few months.


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## gravy9

Thank you very much, Alex, for your comments. 

Just a bit concerned about the impact when I make the changes. I will make the changes and post the updates.

regards,
Ravi


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## gravy9

Update:

I have a few Red Cherry Shrimps, 3 Caridina Japonica and 3 Otocinclus Affinis in the tank now. Will be adding 4 Cardinal Tetras to the tank in a few days.

Things are going well so far and the water hasn't been changed for 3 weeks now. I have removed the CO2 supply for the tank.

*Question*: The water is slightly yellowish in the tank. Is this natural?

regards,
Ravi


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## plantblr

Hey Ravi........

Nice to see your thread & the progress on your DW tank.....

Ravi,setting up & maintaining DW tanks is really simple.
In my case I just bought some cheap potting soil from a nursery after confirming that there are no added ferts in it.Let it dry in the sun for 4 days.Layed it on the bottom for 2",covered it with sand for 2".I put a plate on the bottom,slowly filled it with water for 10",planted the plants & filled it completely with water.For the next 2-3 days I kept on adding plants.I let it cycle for 15days with the powerhead filter running,did a 30% water change.Added fish only after 20days.
My lighting is 3WPG for 10hrs a day,no direct sunlight.No CO2,no ferts dosing.I do a 25% water change once a month.Adding CO2 is like injecting steroids to your plants & not growing them naturally,its a add-on expense,maintainence,attention ....etc.

Thats it........my tank is doing wonders now.You just need to have patience 

Thanks
Ravi


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## gravy9

Thank you for your comments, Ravi.

For my tank, I currently have about 2 wpg light and the tank is placed by a South-facing window to get the natural sunlight. 

I did make the mistake of adding DIY CO2 to the NPT.

As of now, the Cherry shrimp, Amano shrimp and the Otos are doing fine and are healthy. I've been feeding them blanched zucchini and brussel sprouts. In addition, I've been adding some flakes to contribute to the tank as fertilizer when they break down.

Thoughts, comments, ...?

regards,
Ravi


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## plantblr

Nothing much to do Ravi.
Just add some fast growing plants to keep the algae away.Keep your lights on for atleast 10hrs a day.As per my experience,the plants do good with a 25-30% water change every month as they get some fresh nutrients from the water.
I have a 4" Albino Red-Fin Shark,who is always looking out for algae on the leaves,11 Harlequin Rasboras,4 Cardinal Tetras,6 Purple Emperor Tetras & 4 Pearl Gouramis......they all are a happy family for almost 6 months 
Last but not the least,you can scape your tank which depends on your patience,creativity & search.....
Ravi


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## gravy9

Thank you for your response, Ravi.

One of my goals with going to NPT was to experience for myself to go the very low-tech way. Based on Ms. Walstad's book, once you get past the first 2 or 3 months, you can minimize the water changes to once every 4 or 5 months. In my experimental mood, I added DIY CO2, which I should not have done in the first place.

As for scaping, I did not start with any plan on the plant placements. However, now I'm noticing that the tank being a 20-Long, I'm running out of room in the top for the Amazon sword.

Anyway, here's teh update:
1. Removed the CO2
2. Added 3 Caridina Japonica (Amano Shrimp)
3. Added 3 Otocinclus
4. Added 6 Cherry Shrimps
5. Added 4 Paracheirodon axelrodi (Cardinal Tetra)

The tank is stable and going well so far. The fishand the shrimps are healthy. I'm adding some extra food to supplement as fertilizer.

Thank you for all the help and comments. This has helped me learn so much. 

_Question: The water is slightly yellowish. Is this normal and expected?_

I'll add some pictures of the tank soon.

regards,
Ravi


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## plantblr

Initially even I had this problem of water turning Brownish Yellow.I think this was due to some extract from the bottom layer soil entering the water column.I din't find any deaths in the tank.I had to just do some weekly water changes for about 2 months & now I see its fine.So don't worry.Just stick to some water changes & the rest would be ok.

Here is an update of my tank.I did some trimming & removed some plants from the front which had over crowded.Pushed all the Crypts to the right,added a Nuphur Japonica & some sore of a round leaved Amazon.

http://www.flickr.com/photos/[email protected]/?saved=1

Ravi


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## gravy9

Will probably have to do another water change, I think. Will do that this weekend. The fishes and the shrimps are doing fine.


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## gasteriaphile

plantblr said:


> In my case I just bought some cheap potting soil from a nursery after confirming that there are no added ferts in it.Let it dry in the sun for 4 days.Layed it on the bottom for 2",covered it with sand for 2".I put a plate on the bottom,slowly filled it with water for 10",planted the plants & filled it completely with water.For the next 2-3 days I kept on adding plants.


Hi all. Just joined. Am currently (Nov. 25) apprx. where Ravi was in August: i.e. beginning 
This is a perfect forum and thread for me, 'cause it is current. There have been so many I've read over the past month that are dated 2003, 2005, LOL. And then on top of that, this thread is frequented by The Woman Herself :cheer2:

I bet that I am going to get my number one question answered. And my question may indicate a hang-up of sorts, I can see how that might be. Anyhoo...

My question has to do with planting. And please keep in mind, will y'all?, that I am an ornamental horticulturist and botanist - completely terrestrial! So a little knowledge...is....dangerous  Using the 'hi-tech' approach obviates my question. Using low-tech generates it.

*How does one plant the plants in the low tech approach without getting the soil substrate all stirred up?*

Parenthetically: I did see Betty's Hex tank demo. She planted her plants with the substrate barely wetted (and this may help with not stirring up soil). This is OK, as far as I can see, when the plants are rosette-types and/or those that can grow emersed, and hence, have some stiffness to their foliage. But with the stem types, and obligate submersed types, it seems to me that it would be awkward and challenging to plant them without the water to buoy them.

My image is that plants should be planted by making some sort of small depression, space, hole, whatever you want to call it, so as to be able to spread out the roots somewhat before pulling the substrates back over them. Doing it this way I can't see how I am not going to stir up the soil and get cloudiness, etc. Not to mention unintentionally mixing the top gravel layer with the soil layer.

Does all this make sense? I won't even get into the other stuff I am wondering about. Or begin to commune publically with Ravi (he is already in my mind my brother-in-spirit! we have a tendency to do things the same: research first! plants first then fish LOL ).


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## gravy9

Glad to find a colleague who experiments too.  

Anyway, in my tank, I have topped the substrate with an inch of aquarium sand. You could use regular play sand, but have to be careful to make sure that it doesn't contain anything that affects the water parameters. The advantage I see is that when you plant the free flowing soil quickly covers the gap up before any stirring up of the dirt happens. I've also planted quite a bit of Glosso in the tank and that went well as I used a pair of forceps. They're growing like crazy.

However, pulling out a plant is a completely different question.:mod: That said, you can empty about 80% of the water, uproot the right plants, let it settle, move some sand over the dirt and refill. I have to do this next week as I'm redoing my 38-gallon tank (has a UGF and have to remove it) and going with Mineralized Soil Substrate. Let's see how the uprooting goes. I may just decide to trim the plants and plant the trimmings.

Good Luck and welcome to the club.:clap2:

regards,
Ravi


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## gasteriaphile

*Walstad-Method Tank: WATER CONDITIONER?*

Thank you Ravi! I do see what you are telling me. Also, by the way, I read over the process of "mineralizing" soil and intuitively I resonated with that. It just makes sense. For instance, re: the question of the newly submerged soil "chaos" - mineralizing the soil gets that submerged process going beforehand, as far as I can tell.

I have a very straightforward question for Diana. So I hope she is tuned in. In your book, in the section VIII on Substrate, page 138, you wrote:

_"I usually let the tank run overnight with the heater, lights and filter hooked up. The next day I'll add a water conditioner and the fish..."._

I looked everywhere in the rest of the book to find out what you mean by a "water conditioner" and couldn't find any other reference to same! So, what is it?


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## mommyeireanne

'Water Conditioner' is mainly sold for dechlorinating tap water. It also has some ammonia binding property. Not enough for the ammonia from fish waste, but enough to catch the ammonia that is given off from the dechlorination process. It also has binders to reduce heavy metal toxicity in water. 

On my last set up (Oct 5). I topped the dirt with gravel and filled the tank to about 4 inches of water. The stem plants lay down, but they all stayed wet. I also used forceps for the first time. It made such a difference! Almost no dirt escaped into the water in three hours of planting.


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## gravy9

Update on the tank folks:

When I rebuilt my 38-g tank with the mineralized substrate, I had a spare Marineland Biowheel Filter. Based on Diana's recommendation earlier, I added the filter to the tank and removed the powerhead that I had in the NPT before. Wow, what a difference. It's night and day. The tank had a lot of green water over the past two months and as soon as I added the filter, the water was crystal clear the next morning. The tank is very healthy with very little green algae now.

I have 3 Rosy barbs, 8 Harlequin Rasboras, 2 SAEs, 2 Otos and a few Red Cherry Shrimp in the 20 Long. All of them seem to be very happy in the tank.

Here's the picture of the tank from yesterday:









Thank you for your comments, critiques and suggestions.


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## rosse

hey gravy9 and everyone,

I was reading this thread and was just curious. I can't understand why would green water be so dramatically affected by this last filter change of yours.

As I understood, you had simple mechanic filter running in your 20g NPT for water movement, and then just removed it - right? Or did you install bio-wheel filter to this tank afterwards?

In any case, - how could it have cleared algae in one night? With less water movement, there is just less water/air mixing, and this probably results in more CO2 in your tank. Could it be that your mechanic filter was way too powerful, causing CO2 shortage in your tank, and after you've changed it, more CO2 was available to plants to fight algae?

And if you installed bio-wheel filter, well it just provided a medium for bacteria to grow and metabolise organic waste etc, but looking at your tank's picture, it seems that there's enough surface for bacteria to attach to already.

As I said, i'm just curious of this case, and if I'm missing something, it would be nice to hear any thoughts.

Btw, it looks like your tank is doing really well, gravy9! I hope it keeps on going like this!

Simas


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## gravy9

rosse said:


> hey gravy9 and everyone,
> 
> I was reading this thread and was just curious. I can't understand why would green water be so dramatically affected by this last filter change of yours.
> 
> As I understood, you had simple mechanic filter running in your 20g NPT for water movement, and then just removed it - right? Or did you install bio-wheel filter to this tank afterwards?


Hi Simas,

I did not have a filter before. I only had a powerhead in the tank for water movement in the tank. I probably did not experience the green water initially (during the first 3 months) because I was changing the water frequently until all the nutrient leaks were done. It started after I stopped changing the water.

All I had done to the tank was remove the powerhead and installed a biowheel filter at the same time.

Two reasons I can think of for the greening of the water are (1) Since the power head was lower in the tank there was not surface agitation and had minimal surface air intake and (2) The tank was getting too much sunlight in addition to the fluorescent lights



rosse said:


> In any case, - how could it have cleared algae in one night? With less water movement, there is just less water/air mixing, and this probably results in more CO2 in your tank. Could it be that your mechanic filter was way too powerful, causing CO2 shortage in your tank, and after you've changed it, more CO2 was available to plants to fight algae?
> 
> And if you installed bio-wheel filter, well it just provided a medium for bacteria to grow and metabolise organic waste etc, but looking at your tank's picture, it seems that there's enough surface for bacteria to attach to already.
> 
> As I said, i'm just curious of this case, and if I'm missing something, it would be nice to hear any thoughts.
> 
> Btw, it looks like your tank is doing really well, gravy9! I hope it keeps on going like this!
> 
> Simas


I wouldn't say that it cleared the algae in the tank. It just removed the green water and made it clear.

Also, the biowheel filter was preestablished in my 38-gal tank. I just moved it to this tank after rebuilding the other tank. As for the power, it may be a bit too powerful for this 20-gal tank. The difference that this filter makes to the NPT would have been the preestablished bacterial colony along with a lot more water movement in the tank.

Does this explain the clearing up.

Thank you for analyzing the changes. I did not think too much into it myself. Thank you for the feedback.


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