severum mama
Aquarium Advice Addict
If you can't afford a canister for your 55 gallon, the Aquaclear 500 would probably be your best bet. Or, you could probably get by with the Emperor 400, but in my case I added the Emperor 280 as well. If you can afford a canister, a Fluval 404, Rena Filstar XP3, or one of the Eheims would be great for you I'm sure.