First season as a pool owner, the house we bought had 23,000 gallon, with a Tagelus TA-40 filter. I have noticed that when I vacuum up dead leaves, I can see bits of the leaves coming back through the return jets. Recently, I've been fighting some algae and noticed the same thing. If I vacuum up a large area of algae, I can see bits of it shooting back through the return jets. I had a pool store come out and replace the and and install disconnects on the PVC so I can do it myself next time, but it still does it. I tried adding a cup of DE to my skimmer, but after about a minute, I see it shoot out as a white cloud from the return jets. I've been fighting algae for a while now, but following the SLAM procedure on this site, to no avail. I get the feeling that my filter isn't doing anything. What else should I be looking at?