Hi guys new here and I have learned A LOT!!! Currently have to vaccum my 18K gallon pool daily. Get a build up of a brownish yellow "dust" on pool bottom. THought it was algae, but it stay to the bottom and does not move up walls, thought maybe pollen, but thaqt would be a lot of pollen everyday. My question is I use the bleach and acid from the BBB system, and have concretet garden brincks holding my wedding cake steps down. Could the by deteriorating and adding to this problem? Other ideas or help? Need to cleaqn my filter after everyvaccum session or it just spits it back out.

Welcome to TFP!

To really help you, we need to know your latest test results, particularly chlorine and CYA.

What you are describing sounds like you have algae that you are barely keeping under control. You constantly have dead algae falling out of the water and settling on the bottom.

Sounds like algae to me too.
Throw up some test results and maybe even run an OCLT.
That'll let us know what's going on.