I was just about to check out on BRS with a nero 5. I need some supplemental flow and one of these would do the trick however i have 1/2 low iron glass. I chatted with BRS and at first they gave me a vague answer, "1/2 glass is pretty thick for magnets". So i asked if they were confirming people are having issues with the nero 5 on 1/2 glass, and they replied back "Yes people are having issues with 1/2 glass". My Gyre magnets will break the glass if i left go to fast same with my hammer head algae cleaner. It's unfortunate because i like the low profile design, but i cleared my cart and will hold off, even at the $50 discount.