Comments about Mag-Float Acrylic Safe Floating Magnetic Aquarium Cleaner:
NIce! When I recieved the magnet I decided to try it out immediately even though I don't have a problem with algae or dirty water. There must've been some very subtle film on my tank because my sparkling water looked absolutely crystaline after I used the magnet.
Just a side note, the magnet sold here is very small-not even 2 inches in length but not a problem. I used it on my forty gallon acrylic and it took literally minutes.