I took a swing at making a sponge filter yesterday. I cut a small pop bottle off at the neck, cut some slits near the base, put in some larger rocks, then some foam, then topped it off with gravel (all from an established tank) and stuck an air line with a small stone down the middle of it. I'm letting it run with the HOB
until the tank is finished cycling. Will this setup be enough to keep the water parameters good once it is established? It is a five gallon tank that will hold guppy fry.
I want to steer away from the HOB
as it causes a lot of turbulence in that little tank.