Filtration Question

[CHEAPREEF]

If you leave the sponge too long it will become a nitrate factory, just like the bio ball idea. It would be good for a FOWLR but not for a reef setup. On my 7gal i run filter flose in my aquaclear 500, replace it every week. I wouldn't run carbon unless you have too, if you put medication in the tank ect.. If you do run carbon you have to change it out every few days.

Clinton