I was wondering if I should get a mag125 or mag300 for my 90gallon with 3/8" glass. The 125 should work but I was wondering if there is advantage to the stronger magnet doing a better job or just more risk of scratching?
I have personally never had any issues concerning scratching of the glass in any of my aquariums with the Mag Float. I agree with rob thought the bigger the magnet the better it is at getting the hard to scrap stuff off.