Most ammonia tolerant fish species? Or species for unfiltered tanks?

All tanks are "filtered" one way or the other. The nitrates/nitrites find there home on something in the tank, but filter media is the best. I would highly discourage no filtration.

:iagree:

It depends heavily on the plant density, tank size, water change regiment, etc. It wont work by just throwing any "hardy" fish into any tank and have them live for a specified period of time...not only that but one could argue that they're never going to thrive, just survive.

Anyways as for ammonia tolerance...I personally don't think it should ever come down to it, but my zebra danios pretty much lived through every mistake I made.

Jakezori said:

All tanks are "filtered" one way or the other. The nitrates/nitrites find there home on something in the tank, but filter media is the best. I would highly discourage no filtration.

Click to expand...

I assume you are referring to the actual bacteria since nitrite and nitrate are not living :grinyes:

yeah, the bacteria. Sorry. :hitting:

Why do you not want to have a filter?

The only way I would conceive of an "unfiltered" tank being succesful is if the natural filtration (ie: plants) was high enough, and the bioload low enough that there was no detectable ammonia. In other words a balanced ecosystem (aka: The Walstad Method).

Any level of ammonia can cause gill damage.

I would recommend a filter unless you're willing to do large daily water changes and/or extremely low bioload with plenty of plants.

A mudskipper tank maybe?