Hi all, I have what I (and a few others) suspect is mustard algae in my saltwater fiberglass pool. The mustard algae is on the pool floor and steps. I don't think this is dust. There's no similar dust on stuff near my pool. So I started slamming. My test numbers are all good, it sucks that I have to do this to a pool that has crystal clear water. Now that i've begun shocking, my sand filter psi is dropping really low, which never happens. The normal psi is 12. With shocking it's at 3. So, i backwashed and it went back to 12, only to go back down to 3 within 45 mins. I've done this backwashing three times already now whilst shocking. Anyone know why this is happening? There's no blockages (I even checked, and had to reprime). So confusing as to why it's happening.