i would reduce feeding to once a day this will be more than ok. for 6 fish to produce so much waste in 24 hrs seems a bit odd... if this is all your feeding then your defo not overfeeding but it does seem very strange for 4 small guppies and 2 corys which between them should hardly give off much waste at all!4 Guppies, 2 corys.
They get fed twice a day. The guppies get guppy gran or small flakes and the corys get half an algae wafer. The guppies get 2 flakes crushed between them or 8 granuels (2 each). Is this to much? The corys
get half a wafer between to days because they don't finish it all in 1 night.
Xxx~misscosmo~xxX
i have a cory tank containing 10 corys and hardly ever see any poop at all, i do a 30% water change weekly and vac the sand, there are also mts and a few shrimps in the tank too.
do you have really light gravel?