Well, here is the latest:
Postponed putting the grids back in Saturday. Tried doing the chlorine drop once more.
FC = 59 drops / CC = 5-6. I don't have that much FC in pool. The quick test shows a strong yellow. I can remember in past years many times showing orange; that's with a 3 gal shock.
Put grids back in Sunday. Increase DE back to my bucket measurement of 7.5 from 6 last time; mix w/water again (Only 2nd time done this way). Tank pressure @9lb. W/sweep = 11lb. Running pump @2600 ; sweep running well. 2-3 hours later, checked pump and sweep. Filter up to about 16 or 17 lbs. Sweep has dropped to zero.
Same as happened weeks ago... Low water pressure on pool outlet. Turned off sweep = a bit better. Ran pump most of the time. Eventually pressure up to 24lb. (I C more blue in deep end; not so much shallow.)
OK. Lots of dead algae in pool = the why. (Pool problems similar to when I 1st started TFP w/questions.)
Next day, Monday. Pulled out grids. See my pics, July 28, #57. Seems they're worse. Thin coating of DE on half or more of the grids, and not that much on the rest. 1/16 or 1/8". If I remember correctly, it seems that I should have like 1/4 inch or more (I'll google for normal pics)....
Monday pm put everything back together. 7.5 DE powder, small trowel at a time into skimmer w/good water .swirl. Turned on same as yesterday. Checked couple hours later. Again, tank pressure up/flow down.
Tuesday. Tired of cleaning filter n' ran out of DE. Running pump off and on.
Have noticed that if I turn pump off for awhile, then turn it back on, some water flow for ? minutes.
(Pool no longer green. Whats the solution <G> .
I took pics of pool today, when shaded. (May have been better w/full sun.)