Green particles = algae

Brown, white, or gray particles = minerals or dirt.

If your cartridges are dead (see this thread: http://www.poolforum.com/pf2/showthr....-How-to-clean), dirt and mineral particles will go right through.

1. You need to get a good testkit, ie a Taylor K2006. See link in my signature. These are NOT available locally, in any city we've heard of. Test your water ASAP. Test strips aren't accurate enough to help much.

2. Call your water company, and find out if you have high levels of calcium, magnesium, silica . . . or other minerals that will build up in pool water. This is a fairly common problem in AZ, due to poor quality water AND high rates of evaporation (which concentrates minerals in your pool -- same process that creates 'salt lakes').

3. If your cartridges are dead replace them ASAP. Purchase ONLY Filbur or Unicel OR genuine OEM cartridges. Filber or Unicel make most OEM cartridges, but the other after market cartridges range from somewhat lower in quality to really terrible. No-name (Chinese) brands usually seem to be AWFUL. Once you have good new cartridges, read this post [ http://www.poolforum.com/pf2/showthread.php?22458 ] so they last.

4. Tell us what you find (water color, cartridge condition, water co. info, etc.)