[mike31154]

What type/brand of canister filter is it? I currently do not have a sump, nor phos/carbon reactors etc. so I use my Rena XP3 canister with empty baskets for a little extra water volume and flow. I also throw a bag of carbon & GFO into it from time to time. Yes it needs cleaning, but so do most skimmers and sumps at some point. The XP3 is simple to disconnect & clean since it's just a single compartment with square baskets that have a fairly open screen pattern. A while back I replaced the XP3 top/motor with an XP2 since either will fit the container. This was to reduce flow a little to allow the GFO bag more contact time for phosphate removal.

I have no personal experience with Fluval canisters, but the models I've seen appear to have a complex chamber system which could be a pain to clean as stated by others in the thread. As I said, the Rena is pretty simple to clean. When I started the tank I ran it with all the manufacturer's recommended media since I didn't know any better. Once I heard about the nitrate trap business I took everything out but even after running it empty for some time could not detect any reduction in nitrates. Nitrates finally dropped in my system after I added a ball of chaeto to the DT. I'm still running the canister and the nitrates currently remain very low to undetectable. This leads me to conclude that either the chaeto was the answer or my live rock & sand bed have finally matured to the point where they can handle all the nutrients. Just my experience so far and I'm hesitant to put the blame with regard to nitrates on the canister any longer.

If your canister is relatively easy to disconnect & clean it may still be worthwile to use it for running carbon or GFO.