Al
I have 2 FX4's one for each 75G tank and they seem to work fine. I added a spray bar to them and they been running for a couple of years now. I clean them every couple of months since the both have prefilter instead of the factory intake. I mostly have sponge filtration no polishing or carbon since I have well water the carbon is useless. I do have some Seachem matrix in one tray but that's soon to be gone the matrix eventually clogs up. They are easy to clean, I have them on rolling small tables so I just roll to the sink to clean. I used to have them connected to the drain ( see pic) so I can empty for water changes but it drained slow so I opted to use a pump now. I will be using for 90G tank at least in the beginning until I decide if I want to go with wet/dry or stick with the canister.
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