Aquaclears are great HOB filters. For goldfish, it is generally recommended that you use twice the filter power normally used for a tank's size. So, if you had a 50 gallon tank, you would want to use a 100 gallon-capable filter or two 50-gallon filters or more. Since the Aquaclear 110 has a range of 60-110, you may consider adding slightly more filtration, but it should be adequate. A canister filter for a goldfish tank is never a bad choice either!