Thinking of using this filtration on two 20 longs. As I dont have space around tanks for HOB filters and no space for canister. Either 100 or 200gph. Anyone use same filtration?
I do not use sponge filters with a powerhead. I only use small ones for my betta and tetra tanks. I have seen a powerhead used with a sponge filter before and it works. What are you going to be stocking the tanks with? Sponge filters are not the best at handling heavy bioload.
I've used it, works very effectively. Sponge gets dirty quick, but if you're on top of maintenance that's pretty much a non issue, unless you overload it
Sponge filter is best run with an air pump for biological only. Running a sponge filter with a power head will clog it up quickly and shorten its life. You don't need mechanical filtration for 20L, just use the the sponge for biological and do regular WC and substrate vacuuming to accomplish mechanical.
I think a couple of bubblers would work, a reversed UG system work well also, and use the power head sponge as your mech, just need to clean every week with your water changes and vacuum.
This will work fine especially if you have substrate in the tank for bacteria to root. Sponges (sponge type medias) are great because you can clean with easy maintenance. Most have venturis in regards to oxygen. If your worried about over burning... which I wouldn't be... you can always put it on a timer.