I need HOB suggestions for 55g.

Going from a canister filter to a HOB is like going from a car to a horse and buggy.. There is no reason you can't make the canister work.. Anyone looking for an excellent canister should look at Rena Filstars..
 
HOT Magnum needs 4.25-4.5 inches behind the tank. Would be a tight fit for you, but I like mine a lot.
 
Corax, I do not agree with you, Not everyone needs to have canisters. I do not have a problem servicing my HOB's weekly. I feel that i have a better handle of the condition of my tanks when servicing weekly vs monthly as with canisters. I'm also not a fan of the multiple connections that could fail vs a unit that is self contained. I'm not bashing canisters but i do feel for some people and applications HOB may work better.
 
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