How To Reduce Ammonia In A Filterless Tank?

I have a 5.9 gallon that I setup using leftover gravel/substrate/plants from my other tank for the intent of keeping only red cherry shrimps in it. There's just one issue with it, my ammonia levels are around 3mg/l (don't worry, I haven't added any livestock to it yet!). I'm guessing this is from either some of the plant bits decomposing or the plant substrate leaching ammonia. I don't have a filter in this tank so I'm not sure of ways to establish a beneficial bacteria colony in it so does anyone have any ideas or tips?

Like said, I have another tank that I could "borrow" water from, its a mature tank with pristine water conditions but I'm unsure if the ammonia levels would creep back up again. Also unsure if keeping a bit of filter media from the other tank would help.

 

Without any kind of water agitation it will take a long time for ammonia to come back down if it even does. A lack of gas exchange in the water which will kill your plants in time as well. Get an airstone in a corner at the very least. You really do need something to move the water or it will become stagnant and stink and things won't live aside from nasty anaerobic bacteria.

 

iirc, cherry shrimps are super sensitive when it comes to ammonia, nitrites, and nitrates. even a little bit of the first two will kill them. i'd recommend a small sponge filter. that way you have both aeration and a place that'll store bb. you can adjust the flow to very low if you need to.

 

Plants, like in the walstad method. Bacteria will grow in a soil substrate as well, regardless of filtration.

 

Plants, like in the walstad method. Bacteria will grow in a soil substrate as well, regardless of filtration.

While he doesn't need actual filtration he does need some sort of surface agitation for gas exchange.

 

While he doesn't need actual filtration he does need some sort of surface agitation for gas exchange.

I agree water movement is beneficial for both the plants and shrimp, but gas exchange happens even when the surface is still.

 

The exchange in still water is only through diffusion and is too inefficient for cellular respiration. It's the reason stagnate pools of water become poisonous. While plants might survive, they won't do well and nothing above microbes will be able to live in it for any real amount of time. Outdoors you have wind that can assist but indoors you absolutely need some sort of water agitation for the exchange to take place at levels suitable for life.

 

I don't have a filter in this tank so I'm not sure of ways to establish a in it so does anyone have any ideas or tips?

The bacteria will colonise most (if not all) surfaces, including glass, driftwood, substrate, etc. and they'll also disperse throughout the water column. In general, with shrimp's low rates of ammonia excretion, there shouldn't be significant issues related to ammonia/nitrite/nitrate accumulation that regular water changes won't resolve.

With your present 3 mg/L concentration of ammonia, I would recommend very large water changes to continuously dilute it, as you might be waiting from here to the Second Coming to have bacteria process it to nitrate without a filter.

I agree water movement is beneficial for both the plants and shrimp, but gas exchange happens even when the surface is still.

Agreed, very beneficial, but not necessary. There's plenty of owners with filterless heavily planted nano-tanks on planted tank with very minimalist set-ups: no heater, no filter, no powerhead, no pump for circulation. They don't report significant issues with their set-ups.

 

So in short:
-Change the water a lot
-Provide some sort of water movement
Should have an air pump lying around somewhere so will throw that in there, thanks for the help!

 

So in short:
-Change the water a lot
-Provide some sort of water movement
Should have an air pump lying around somewhere so will throw that in there, thanks for the help!

If you have an airpump just stick a sponge filter on the end and cycle the tank. Then you won't have issues.