For years I have had a 450 gallon FOWLR
acrylic tank. As you can imagine, this is a very large surface area to keep clean. I was using a Mag Float rated for my 3/4" thick acrylic. This worked fine for a long time. I more recently have a much more stubborn algae that would not come off with the magnet. I had to go in with a hand scrubber and this was brutal.
My only idea here is that this is more of a calcareous algae since I have raised my Ca
+ levels in recent past in an effort to promote corraline growth. I'm also considering adding some beginner corals which is why I have raised the Ca
I just got a new Mag Float Professional magnet that is rated for tanks starting at 1.5" thickness and even that magnet is not easily removing the algae. With many back and forths around a circle it eventually comes off. This is not easy but it's better than using a hand brush.
So, just looking for thoughts from everyone. Am I on to something regarding the Ca
+ levels causing a more difficult algae to form?
One last thing, the snails in the tank are able to eat this algae. You can see their classic markings from eating all of the place.