Magnet algae scrappers are good but big warning. I got a nasty scratch on the glass by not noticing a TINY peace of grit or something had got into one. Now I just use the algae remover pads you can buy and a bit of energy and clean the glass each water change (once a week) . No probs now. For deep tanks they sell them on the end of a stick. Because you rinse them each time you use them there is much less chance of trapping something nasty.The magnet algae scrapers are fantabulous !!
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