I have a HOT Magnum filter for my 46 gallon and it works great. For biological filtration there is a filter called a Bio Wheel Pro 30 or 60 that easily connects to your HOT Magnum, which create biological filtration. It runs around $30 or so, depends on where you shop around. You can also look it up on the internet.
55 Gallon-two clown knifefish, chocolate pleco
46 Gallon Bow Front-Planted-swords, java fern and African cichlids, sail fin pleco
29 Gallon-black ghost knifefish, bristlenose pleco
10 gallon-brackish, figure-eight puffer, knight goby