1. Stop going to a pool store with computerized testing -- they'll sell you stuff you don't need, and that may make things worse.

2. Do not add ANYTHING unless you absolutely need it.

3. Purchase (locally) a cheap OTO / phenol red drops testkit, and test chlorine and pH yourself.

4. Open your filter, and wash it down completely. Backwashing DE filters never completely cleans them. If you are dealing with a cloudy pool, you need FULL function.

5. Make sure you do not have a timer turning the pump off. DE filters can be successfully operated with 2 speed pumps, alternating HIGH and LOW, but many do NOT function well with pumps turned ON and OFF.

6. Order a K2006 kit, so you can get away from inaccurate 'computerized' testing: http://pool9.net/testkits/

7. If you want faster responses, subscribe. The season is beginning to take off, and for the next 2 months, we'll have more questions than we have people who can give GOOD answers.