K626;1829612; said:I get that kind of build up on my hob filters. If you take a fine mesh net, and run it over it, it should fall into the net and you can pull most of it out. It also won't scratch your acrylic. Once you get most of it, use an acrylic safe algae pad to remove the rest. I also suggest cleaning your filter, and a really good gravel vaccing.![]()