Back to the subject at hand. There are no filters as effective as a well designed wet / dry system. Most of the better HOBs try to imitate one or another feature of them but can't because they don't have the large sump to work with. If you can use some of the tricks already given to cut the noise of your wet dry to a nice level, that will be your best choice. The next best choice, if you give up on the wet/dry, would be a nice big canister like the Rena XP4 or the large Fluval already mentioned. Canister filters are so quiet that you must put a hand on them to see if they are running, at least my Renas are.

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Fishless cycling

agreed oldman lol the best filter would be wet dry in this situation as there biological filtration is unmatched compared to the bio wheel but hob make a nice addition to other filtration and can certinally keep the tank cleaner