I'm currently using a Magnum 350 Pro on my 85 gallon tank. I really like it. I haven't had a single problem with it yet. That was my main motivation for wanting the new C-360. I wanted to stick with Marineland until I read others comments on the 360. I am currently setting up a new 55 gallon tank and don't have a lot of room in the back behind the light, so I can't make the bio wheels work for me on that tank without splashing my light fixture. Otherwise, I would have gone with another 350 Pro. I do think I will add another 350 canister to my 85 gallon in the near future as a secondary source of filtration (and back up). I have read others comments in the past that they were unable to use the bio wheels because they are connected together and make it difficult if your tank has a center divider (like many of the larger tanks) This is easily fixed. If you take out the "T" fitting between the two bio wheels, you can purchase two "elbows" from AquariumGuys and by using a "y" connector for the tubing in back, I was able to split up my bio wheels. Wish I could make it work on my 55, but I think I have decided on the Eheim 2026.