Thank you. I have had my canister going for 2 years but I also have two HOBs and 3 sponge filters due to my water not being right most of the time so I keep adding different filters. I may have too much filtration, I don’t know. I also have a lot of plants. My guppies have never done well in this tank. I have other aquariums that only have a Hob and 1 sponge they are always good. With platies and mollies in them. I have one bare bottom with a mix of fish 10 gallon for grow out all is well with it. I think I will take off the canister and slow down the filtration and see if it help.