Don't know why flocculant isn't working..


New member
Aug 7, 2020

At the end of spring, we decided to set up our intex above ground pool ( it's a round 12 m³ pool ) and everything went good. After a month, the water started turning really green and we got rid of the algae by shocking, but now there is a lot of stuff dissolved in our pool that turns the water light gray/blue and after a couple of hours , that stuff sinks and forms a dark green/brownish sandlike layer on the bottom of the pool and the water gets clear after it sunk. When we swim in the pool, that layer dissolves back into our pool and the water turns light gray/blue and after a couple of hours, all the dirt sinks back to the bottom. We can't vaccuum that layer out of the pool or get it out by using our filter, so we decided to use flocculant. We put it into our pool at night, set our filter on recirculate for 3 hours while the water was gray and the layer was dissolved. After 3 hours, we turned off our filter and waited untill the next morning. Nothing happened and the same green/brownish layer sunk back to the bottom.

We have no idea what to do... Does someone know what's happening and how to get rid of it?


Bronze Supporter
You need to vacuum that stuff to waste. Slowly sneak up on it and it should vac quite nicely. BE SURE TO VACUUM TO WASTE -- don't let it get into your filter or it will gum the sand up like nobody's business, and you'll have to replace your sand. If you have the dinky cartridge filter that came with the pool, be prepared to throw that cartridge away.

Never use flocculant because of the way it can mess up your filter.

That brownish grey stuff is dead algae. Sounds to me like you need a good SLAM Process. You'll need a good test kit to do this, so get either the TF-100 or Taylor K-2006C, links in my signature below. Don't try to SLAM using guess strips or pool store testing. They're useless and notoriously unreliable for anything, much less a SLAM.

You'll continue to see the dead algae drop out of the water until it's all dead. Just keep vac'ing and brushing until it's gone.