what is the best algae scrapers for bow front

Use side to side motions - not up and down. Then the rounded glass is not a problem.
 
I use a mag float on my 46BF and have no trouble. Good luck.
 
I use a small piece of the finest steel wool you can buy, I think it's a grade #0000. I take a small piece, wet it and rinse it well first, tuck the straggley ends (from tearing it off) together to make a ball and....works like a charm not only on my bowfront, but all the tanks. I get some direct sun on all my tanks so I get a big of the spot algae that needs to be scraped every week.
 
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