I’ve had MA in my pool for at least 3 years now nonstop. I’ve just never been able to get rid of it. I’ve been reading the forums on here for a few years as well. I have a sand filter and we changed the sand to zeolite about 3-4 years ago. I literally just found out last night on here that you can deep clean your filter so, I think that may be my next move however, I have been slamming my pool for a few days shy of 1 month now. My liner is taking a beating with all the liquid bleach. I have passed the OCLT test several times and have had 0 CC since day 7. The Mustard Algae has always been on the bottom only, never on the sides or anywhere else. Also, up until I started the slam r the MA would only fall to the bottom when the filter was running. The bottom would remain clear when the motor was not running. I haven’t cut the filter off since the beginning of the slam. I try to vacuum to waste as often as I can. I brush at least once a day. I backwash and rinse often. My pressure gauge isn’t working properly so I can’t really go by that. My pool has remained balanced except for the Calcium hardness, I do have to put more of that in. During the regular slam my CYA started off at 58 and now is around 37. I use Pool Math everyday. I have been MA slamming for about a week now. I’ve tried to keep my chlorine level up to around 24ppm. I’m going to try to attach a photo of what the MA looks like. At times there is only a handful of spots and other times there are too many to count. A lot of them look whitish, which I believe is dead algae and others look like sand. I’m honestly at a loss. I live in Alabama so we do have a ton of pollen and we just cut down two cedar trees by the pool. My hubby mows the grass in our back yard so contaminants from that fly in the pool. Also, there are no shaded areas in my pool and everything is out of the pool. I just bought all new pool equipment so I can use it once this algae is gone. I have spent a ton on liquid chlorine. Oh yeah, my second problem to deal with after this is getting rid of those biting flying ants. I bet 1K of those go into my pool on a daily basis. They make you not even want to get i to the pool because they are constantly biting g you. I was stung twice by a red wasp last year. That kept me out of the pool for a while.