Quote Originally Posted by carsona246 View Post
I know you can use stability with fish in the tank, don't know about frogs, but I don't think it would harm them. I'd double check with an aquatic frogger though. It will not be tough on the frogs if you do daily waterchanges. It sounds like your current tank cannot handle the bioload and is getting ammonia as well. If that is the case, the bigger tank will be better regardless. Just do daily waterchanges and it shouldn't bother them so long as ammonia is less than 1 ppm.
Filters can compete for bacteria, but you will still have the same amount of bacteria in the tank as a whole. The bacteria will grow on whatever media has the best conditions for them, regardless of whether that is a filter, an ornament, whatever. Your tank will grow bacteria until there is no longer enough ammonia to support anymore. We use filters because they promote the growth of bacteria, and they help grow the bacteria faster(because the filter has more ideal conditions for bacterial growth). So to answer your question, two filters will not harm the beneficial bacteria growth, it will provide more surface area in general for bacteria to grow on. You may have less bb(beneficial bacteria) in each filter, but the amount in the whole tank will be the same as if you had one huge filter with a ton of bio media. I always like having more than one filter in case one fails, the other can always provide backup, but I usually keep fish who don't mind a little current.
I PM'd two people who are experienced with aquatic frogs. If you know anyone else to talk about this issue to, please have them

Also thanks for the sponge filter information! It is much appreciated.