A No Water Change, Planted Tank?

[BBradbury]

OK. Had to try a planted tank with no water changes. Don't worry, the water chemistry will be tested every few days to make sure no fish are hurt during this experiment. Have read and reread D. C. Johnson's book on using Chinese Evergreens "Aglaonema" emersed to filter out dissolved ammonia, nitrites and nitrates too.

So, I'm using a 45 G tall with a single 6500K 40 watt, T12 tube for the benefit of the existing aquatic plants and emersed two, large, Chinese Evergreens. In theory, the emersed plants will use all the fish waste and with the exception of replacing the water lost to evaporation, no water changes are needed. Ammonia and nitrites will always be "0" and nitrates, again in theory, shouldn't exceed 40 ppm. Fancy Guppies and a few Corydoras should handle this nitrate level with no trouble. At least, that's the current plan.

Attached are some pics of the tank, which is a much smaller version of Johnson's 150 G.

Hey, why not? Above everything else, have fun!

B

 

[titangoddess]

Very cool.. I have seen this done. I am trying to to it to my tank also but I am not doing the semiaquatic plants at all. They all need to be fully aquatic for my tank. The setup I have right now will take months to grow where I no longer need a filter or pump. I am doing a dwarf grass carpet on 2/3 rds of the tank in sand and substraight leaving a gravel seperation to help pull in nutrients from the water to the roots. The roots should get so thick they serve as a filter and literally absorb the waste like a sponge. Good luck on your experiment.

 

[BBradbury]

No Water Change Tank?

For what this information is worth. After two weeks of no water changes, only topping off the tank due to evaporation. Ammonia and nitrites at "0" and nitrates read 10 ppm this morning. Never got those nitrate readings after two weeks of no water water changes in my heavily stocked tank with the old system. Had to change half the tank water every week.

Filtration is strong, but not through the roof. The Chinese Evergreens are growing, so there must be a trace of pollutants being taken in by the plant roots. Aeration is strong and directed at the plant roots.

Carbon medium was put into the filter equipment just to remove any traces of copper or zinc from the water pipes. Apparently, these are toxic to fish. Learn a little something every day.

Fancy Guppies, around 150 or so and some Corydoras that have been in the tank for several years are healthy and active in the 45 G tall.

Feeding is every other day, as much as the fish will eat in a couple of minutes.

The evergreen plants are amazing so far.

B

 

[fort384]

Very cool setup. Keep us apprised of your progress!

 

[MrPillow]

Are you concerned about concentration/loss of other chemicals in the water, aside from nitrogenous waste? Trace elements, hormones, etc.?

 

[BBradbury]

No Water Change Tank?

Are you concerned about concentration/loss of other chemicals in the water, aside from nitrogenous waste? Trace elements, hormones, etc.?

Hello Mr...

You make a good point. Have only been concerned with the ammonia and nitrite levels. I do replace the water lost to evaporation, about two quarts per week. The top off water should replace the phosphates and sulfates. The nitrates are already in the water at low levels. So, that should cover the macro nutrients. As for the micros, I dose a liquid when I top off the tank.

The evergreens should use any other waste products from the fish in the same way they do the other pollutants.

I did notice a small group of new Guppy fry in the tank this morning. No more than a half dozen. My impression is if conditions are right enough for the fish to reproduce, then the general water properties are good.

Time will tell. Thanks for your post.

B

 

[MrPillow]

Are you planning to prune the evergreens regularly, or just let them grow?

 

[BBradbury]

No Water Change Tank?

Hello again Mr...

We've kept Chinese Evergreens for years as house plants and just let them grow. So, the current plan is to let these emersed plants grow. There are 8 to 10 fairly large plants in the tank all about 12 to 14 inches tall and I've seen some pretty fast growth. There are several new leaves just in the past 10 days. The plants have been in the water about three weeks or so.

The tank is heavily stocked and the Corydoras in there are about 3 inches long. Before introducing the plants, I was changing out half the tank water every week in order to keep the water chemistry stable, so this has been a nice change.

B

 

[MrPillow]

I can imagine so I hope you continue to have success with this project. It would be interesting to view data of complete water content over an extended period of time, see just what compounds are ending up where. Cheers!