Hello! I am new to the site and am needing some advice on whether or not this could possibly be brown algae. We have my daughter's birthday party coming up in about a week and a half and I just want to be sure it's safe for everyone to swim. Upon removing our pool cover a few weeks back, there was what I thought was dirt and some leaves in the pool as there were holes in our cover. We couldn't afford to replace our cover (33 ft) once we realized it had the holes and assumed some animal outside had chewed holes through it. Anyway, since opening it up, we've vacuumed it twice now, and I've shocked it at least 4 times. I had the water tested last weekend and the levels were all really good according to the paperwork we were given; the chlorine was high, but I knew that and wasn't worried about that. The brown stuff on the bottom of the pool looked like dirt and upon vacuuming it, it looked a lot better, but 2 days later, it was back, but had reduced considerably. I'm attaching a link to an image of how it looked a few days after vacuuming the first time. We vacuumed again last night and today, I'm starting to notice the dirt/algae again, although it's lessened further. Could it just be dirt that hasn't been sucked through and just settles back to the bottom? Or is there a type of algae that reacts this way? We had mustard algae last year and eventually got that problem resolved, but this isn't the same thing. I'm linking to a picture I took of it yesterday before we finished vacuuming. It's not a great picture, so I'm not sure if it helps at all. We have an above ground 33 ft round pool. Not sure what other information is necessary.
Total Chlorine: 4.4
Free Chlorine: 4.4
Total Alkalinity: 85
Calcium Hardness: 200
Thank you for any help anyone can provide us!