Algae that won’t shift on glass

[StevenF]

A lot of people including myself have found that hard green spot algae does well in tanks with low phosphate levels. I found in my tank a phosphate dose of 1ppm a week after water change prevents this algae in my tank..

 

[Stan510]

To scrub it off,those plastic pot scrubbers,the ones also used in trickle filters? Take that right off the glass or acrylic with no scratches.