What did I do wrong?

[z71silverado98]

bacteria should not be harmed.

another option you might consider is one of the cheap air powered filters as a difuser. i had a few left over from breeding, just gutted it drilled 2 holes in the side to insert suction cups then mounted it w/ the open end facing down. its near the outflow of my filter so there is adequate surface movement. it fills w/ co2 and remains in constant contact w/ the water.

 

[djlen]

Won't affect your bacteria colony and won't harm your filter.
If you look at the lip where the water runs back into the tank from the filter you will see that if you slide a piece to filter sponge over that lip it will deaden the return flow and dramatically cut down on surface agitation.

Len