Currently have two 2217's running on my tank. Looking to increase filtration slightly and add some carbon filtration for the ammonia load, so im thinking of keeping a 2217 and adding a larger filter and selling one of the 2217s, or, just replacing the two and getting one big filter. Whats a good one? Looking at the Eheim advanced filters and the Fluval canisters. I prefer eheim but was told fluval is just as good but cheaper. Thoughs?