Originally Posted by babystarz
They do filter some ammonia, although I'm not sure if a single moss ball will make that much of an impact.
Well, I'm thinking that I do twice weekly water changes in my 3 gallon tank. But on days when I don't do a WC, well, my fish are still producing wastes. If an easy-to-care for moss ball can help remove this, hey, I'll try one. (Or a few 'cause they're kind of cute. LOL)
They're about $8 each at Petsmart.
Bringing it back to the OP's post -- I'd think that a 2.5 gal tank would be fine for a moss ball. Petsmart keeps theirs in Betta cups, and those are tiny little things. Despite this, the balls I've seen look green.