preston5321;4932537; said:Is there an established filter on the tank? you said you recently added a canister filter. Just wondering your tanks not going through a mini cycle or something like that.
This is what I was going to ask. You added a canister but what did you have as your filter before? Did you leave that filter on or transfer your fitler media to the canister? If not then all the beneficial bacteria is gone and your tank is cycling all over again.