# Long term success of NPT method



## AshK (Nov 21, 2008)

I've been reading extensively on the NPT method. I am a firm believer in water changes, so naturally I am reluctant to consider otherwise. A few questions have cropped up that I have been unable to find answers to:

What's the oldest NPT out there? (One that follows the usual guidelines--lack of mechanical filtration and water changes) Do these tanks have long term success? 

How does the NPT method protect against build up of hormones and other nasties?


----------



## bartoli (May 8, 2006)

AshK said:


> What's the oldest NPT out there? (One that follows the usual guidelines--lack of mechanical filtration and water changes) Do these tanks have long term success?


Don't know what is the oldest NPT out there. I have tanks that haven't changed water in years and the fish are doing fine.


----------



## AshK (Nov 21, 2008)

Thanks for they reply. Anyone else have input?


----------



## Dustymac (Apr 26, 2008)

AshK said:


> Thanks for they reply. Anyone else have input?


I stopped changing water more than a year ago. It does take quite a leap of faith if you've been changing water for a long time (in my case...decades). According to the Walstad methodology, the plants absorb the "nasties" (hormones?) from the water with the ultimate removal taking place during pruning. So far I've seen no evidence that isn't happening.

Hope this is helpful,
Jim


----------



## peridot (Feb 24, 2005)

I have a 4 year old NPT and do 40% water changes maybe twice a year. Plants are vigorous and (with UV sterilizer) fish are happy.


----------



## dawntwister (Sep 29, 2007)

I would like to see your tanks Dustymac. Post a link. My NPT only lasted 3 months without a water change. Then BBA took over.


----------



## dwalstad (Apr 14, 2006)

dawntwister said:


> I would like to see your tanks Dustymac. Post a link. My NPT only lasted 3 months without a water change. Then BBA took over.


After setting up 3 new tanks in last new year, I understand your question and your problem. 

For the first 2-3 months, an NPT may need to have water changes, charcoal filtration, etc every 2 weeks. That's because the soil is releasing tons of nutrients first 6-8 weeks (my book, p. 131).

Once the soil has stabilized (the nutrient and possible toxin release has dropped off), you can do water changes much less frequently.

The first 2-3 months are sometimes (but not always) hard to get through.


----------



## dawntwister (Sep 29, 2007)

dwalstad said:


> For the first 2-3 months, an NPT may need to have water changes, charcoal filtration, etc every 2 weeks. That's because the soil is releasing tons of nutrients first 6-8 weeks (my book, p. 131).
> The first 2-3 months are sometimes (but not always) hard to get through.


Possibly there was a reaction with the soil and the water? For the water here is extensively treated. The ph is 8.4 and has no kh or gh is in the tap water.


----------



## colinsk (Dec 29, 2008)

dwalstad said:


> After setting up 3 new tanks in last new year, I understand your question and your problem.
> 
> For the first 2-3 months, an NPT may need to have water changes, charcoal filtration, etc every 2 weeks. That's because the soil is releasing tons of nutrients first 6-8 weeks (my book, p. 131).
> 
> ...


I am about 2 months into my 10 gallon experiment tank. The first month required twice a week 90% water changes. Ammonia was off the top of my test. I assumed there was fertilizer in my soil even though the bag did not list it. I also was leaching tannins from the bark/wood I was not able to remove. About 8 water changes did the trick. I had no fish only plants. A month ago I added 10 Amano shrimp, 2 Zebra Nerites and 12 Boraras Brigittae. Lately, I am doing a 50% change every few weeks to keep the water clear of tannins. (Just for my own aesthetic sense.)

Now it is running fine and about two weeks ago my plants started to emerge and that has helped the aquarium greatly. Before I had aerial growth all the plants were growing very slowly even though I have some very rapid growing plants in there. The chemistry is staying stable. It is running nitrogen limited at the moment. I have a very small fish load right now. I will have to decide how best to increase it.


----------



## dawntwister (Sep 29, 2007)

colinsk said:


> It is running nitrogen limited at the moment.


What does this mean?


----------



## colinsk (Dec 29, 2008)

When I do a water test I have 0 ammonia, 0 nitrites and 0 nitrates. All of the nitrogen being supplied by the fish food is going to grow plants.


----------



## AshK (Nov 21, 2008)

Can we get this back on track? For the record, I'm not referring to the usual big three params. Just because your big three are ok doesnt mean there isn't something horribly wrong with the water....

What about hormones and TDS? Anyone have an answer? Can plants really absorb fish hormones? Any one have TDS readings for their older NPT?


----------



## bartoli (May 8, 2006)

The TDS of my NPTs vary from 270 to 370 microsiemens. It seems to me TDS is NOT correlated with tank water age, but with the frequency of feeding. The least often fed tank tends to have the lowest TDS while the most often fed one tends to have the highest TDS.

If you haven't already, you may want to study Ms. Walstad's book "Ecology of the Planted Aquarium".


----------



## Dustymac (Apr 26, 2008)

dawntwister said:


> I would like to see your tanks Dustymac. Post a link. My NPT only lasted 3 months without a water change. Then BBA took over.


Here's a pic of the last tank set up. 55 gallon established April 2008. It gets 2-4 hours of direct sunlight on sunny days. As far as I remember, it's had one water change shortly after it was set up.

For the record, the pump on the left is not a filter but used for circulation only. The one on the right pumps water through an UV filter. Both have sponge prefilters which get cleaned weekly, and therefore leave all ammonia processing to the plants.


----------



## Dustymac (Apr 26, 2008)

*Npt3*

Here another tank - set up Nov '07, 30 gal. Cheap garden soil under recycled Eco-complete. No direct sunlight, about 2 watts per gallon. This one has the same circulation and UV configuration as the 55 gallon, and hasn't had a water change in over a year. Occasional patches of thread algae and lots of diatoms in the winter from adding so much water. Lots of pruning, otherwise this tank nearly runs itself.

One thing I have noticed that might precipitate a water change is a slight overall drop in ph. 7.3 down to 6.4 in one of the tanks. The fish seem OK but I'm still watching it.


----------



## Dustymac (Apr 26, 2008)

Here's another tank - 45 gallon, not a true NPT because it has a gravel substrate I injected with soil back in October, '07. About 100 3/4" frozen cubes pushed into the gravel around existing plants. Now this tank has a pretty good mulm buildup but the plants still grow slower than they did when it was "hi-tech", and slower than my true NPTs. This tank has one submerged 5 watt UV filter which provides water circulation.

BBA almost killed this tank in the early stages of the transition, but I found that changing water didn't help and only added fresh nutrients to the water column - the algae kept growing and growing. What worked was reducing food (aka fertilizer), reducing light, and adding Duckweed and Frogbit to extract nutrients from the water.


----------



## dwalstad (Apr 14, 2006)

AshK said:


> Can we get this back on track? For the record, I'm not referring to the usual big three params. Just because your big three are ok doesnt mean there isn't something horribly wrong with the water....
> 
> What about hormones and TDS? Anyone have an answer? Can plants really absorb fish hormones? Any one have TDS readings for their older NPT?


Hormones are organic compounds that (like any other organic compound) will be degraded by bacteria.

As to TDS, I did several measurements in 2007 during a major Southeastern drought when changing water threatened to dry up my well. My tapwater had 0.31 mS/cm2 conductivity. The 45 gal (with potting soil underlayer and six months without water changes had conductivity of 0.32). The 50 gal with garden soil had 0.44 mS/cm2.

I believe that salt accumulation depends on the soil underlayer and plant growth. The more organic the soil layer, the more it pulls salts out of the water. Organic soils act like an ion-exchange resin.

AND the better the plants grow, the more they will pull sodium, chloride, and other ions out of the water.

Ecosystems are complicated!


----------



## dawntwister (Sep 29, 2007)

Dustymac said:


> BBA almost killed this tank in the early stages of the transition, but I found that changing water didn't help and only added fresh nutrients to the water column - the algae kept growing and growing. What worked was reducing food (aka fertilizer), reducing light, and adding Duckweed and Frogbit to extract nutrients from the water.


Interesting!!

BBA is a chronic problem in my tank. First 1 was in a location where it got direct sunlight. Second 1 in a shaded area of living room. Got BBA under control adding KNO3, Flourish comprehensive and increasing circulation. I think since tap water has high ph and no minerals, it must heavily treated with chemicals. Lack of minerals causes it to grow like weeds in a garden.


----------



## dawntwister (Sep 29, 2007)

dwalstad said:


> Hormones are organic compounds that (like any other organic compound) will be degraded by bacteria.
> 
> As to TDS, I did several measurements in 2007 during a major Southeastern drought when changing water threatened to dry up my well. My tapwater had 0.31 mS/cm2 conductivity.


What does this mean? Please simplify.

Has anyone used Fertilome Seedling and Cutting Starter dirt or Miracle Gro seed starting potting mix in their NPT?


----------



## colinsk (Dec 29, 2008)

She is saying even after long periods of no water changes TDS were not a problem. Organics in the soil tend to bind to the ions that cause TDS and release them when the water coluum gets low and can disolve them again.


----------



## bartoli (May 8, 2006)

colinsk said:


> Organics in the soil tend to bind to the ions that cause TDS and release them when the water coluum gets low and can disolve them again.


Not sure what that means. Are you suggesting that organics in the soil will prevent TDS from dropping below a certain threshold?


----------



## dawntwister (Sep 29, 2007)

I think this state:
Organics in the soil tend to bind to the ions that cause TDS and release them when the water coluum gets low and can disolve them again.

Means when the TDS is low in the water column they will be released from the soil to create a balance. Like adding potassium nitrate there is a balance between positive and negative ions.


----------



## bartoli (May 8, 2006)

Thanks Dawntwister. I didn't think that soil would keep the water TDS above a certain threshold. Would appreciate if someone can comment about the mechanism behind.


----------



## colinsk (Dec 29, 2008)

This article explains more than I know:

http://www.spectrumanalytic.com/support/library/ff/CEC_BpH_and_percent_sat.htm


----------



## bartoli (May 8, 2006)

Thanks Colinsk. Much appreciated!


----------



## EMc/ (Feb 20, 2006)

> What's the oldest NPT out there? (One that follows the usual guidelines--lack of mechanical filtration and water changes) Do these tanks have long term success?


OK, all my tanks are only using plants & bacteria for filtration- nothing mechanical. I do water changes a couple times a year, usually (nanos more often). All are well planted, sit by windows & some are also given added fluorescent lighting to augment them. I have 9 of these type tanks set up right now, varying in size from 1G- 55G. I've been keeping tanks like this for about 10 years. I lose track of time, but I have a 48 & a 55G that I'm pretty sure have been going for 2-3 years each. I went longer w/ an angelfish tank once (I think 4-5 years). I got fry from that angel tank (which they ate, but hey, my point was they bred). My diamond tetras bred regularly in long term NPT tanks, too.

One of the more heavily stocked tanks I have is the 55G. It has several large rocks & fossils in it, so I'm not sure what the net water amount is- probably ~35G. I have 2 large, adult, wild caught Peruvian Angelfish in this tank- they've been in there for a little over a year. There were 3, but after they paired off, the larger one kept picking on one of the smaller ones, & I thought it was harmless & would be OK, but I'm pretty sure a fishie murder happened. Anyway, no further problems w/ the angels. There's also 5 adult bristlenose (raised since they were juveniles) & 2 cory cats, a few platies, & some endlers in there. All seem "happy"/ active. Bristlenose trying to breed (laid eggs & guarded- no fry that I saw).

I kept GBRs in this type of tank, too. Everybody talks about how difficult it is to keep GBRs & how pristine the tank must be kept, frequent water changes a "must", etc... I raised 6 from very young juvies... all seemed fine... I had a heater outage this winter & lost them (still have one that was in different tank). They were in w/ betta coccinas, which survived the cold temps. I had mine for a year & was hoping to breed them. Have some ordered & will try again.

Marty

http://NaturalAquariums.com


----------



## prBrianpr (Nov 18, 2007)

Everyone is missing bacteria, bacteria is the more important part, heterotropic bacteria live near roots. Roots pump oxigen into substrate and the bateria can grow. This bacteria feed from soil organic components and transfrom it to inorganic. The this inorganic components is absorved by the plant roots. there are a cycle. fish food are the primary material, the final product is plant bio-mass. We can have a complete ecosystem if the fish eats plants an a rate that the plant can grow again and produces enough food for the fish. I have something similar but not with fish. I have little bugs that eats the died leaves of plants. there not are fish, and take sunlight. I encounter Iron deficency and I begins to add iron.


----------



## EMc/ (Feb 20, 2006)

> Everyone is missing bacteria, bacteria is the more important part...


Uh... not me, Brian!  Read the first sentence I wrote:



> OK, all my tanks are only using plants & bacteria for filtration- nothing mechanical.


Marty


----------

