Here is the situation. This is a second year AGP with SWG, and this year the water has been A to A- all summer. The water's been really good, but the bottom of the pool constantly has this stuff that I have debated over and over whether it is pollen/dirt, or mustard algae. This started at the end of the season last year and has been constant this summer. I can vacuum all that stuff up, and within an hour I see it forming again in clumps. I keep the FC in the 7-9 range, CC is always 0, CYA is 70 and pH is about 7.5. I've done one SLAM and it made no difference.
So yesterday evening I decided to give it one good vacuum and get the FC up a little bit, then shut the pump down for 24 hours. All day today, no sign of the "stuff". I turned the pump on this evening and within 30 minutes I could see it forming again. So to me, it seems to be coming FROM the sand filter.
What is the most reasonable solution in this situation? That the filter is catching pollen, but somehow it blows it back into the pool? Or maybe a significant percentage of the water being pumped into the filter isn't going through the sand? Or is it possible that "stuff" is actually growing in the sand filter and then I am pumping that into the pool?
Another observation - I also had the "inspect cell" light on yesterday, so today I uninstalled and reinstalled it (no issues btw). To take it out, I plugged the return and turned the sand filter MPV to Closed. However I had a constant significant flow of water coming out of the backwash port while in Closed. Is that normal? I assumed that all flow paths were completely closed when the MPV is in Closed. Also, I went ahead and backwashed the filter since I was doing maintenance anyway. Note that I did all of this BEFORE turning the pump on back to normal today (so while the pool surface was still clean).
Lastly - the worst $100 I ever spent was having the pool installers "hard-pipe" the plumbing during installation last year. I've discovered that there is no easy way to open up the filter unless I cut the pipe. Has anyone come up with a solution for easy removal of the top of the filter with the PVC piping?
Thanks in advance for reading, and for the feedback!
So yesterday evening I decided to give it one good vacuum and get the FC up a little bit, then shut the pump down for 24 hours. All day today, no sign of the "stuff". I turned the pump on this evening and within 30 minutes I could see it forming again. So to me, it seems to be coming FROM the sand filter.
What is the most reasonable solution in this situation? That the filter is catching pollen, but somehow it blows it back into the pool? Or maybe a significant percentage of the water being pumped into the filter isn't going through the sand? Or is it possible that "stuff" is actually growing in the sand filter and then I am pumping that into the pool?
Another observation - I also had the "inspect cell" light on yesterday, so today I uninstalled and reinstalled it (no issues btw). To take it out, I plugged the return and turned the sand filter MPV to Closed. However I had a constant significant flow of water coming out of the backwash port while in Closed. Is that normal? I assumed that all flow paths were completely closed when the MPV is in Closed. Also, I went ahead and backwashed the filter since I was doing maintenance anyway. Note that I did all of this BEFORE turning the pump on back to normal today (so while the pool surface was still clean).
Lastly - the worst $100 I ever spent was having the pool installers "hard-pipe" the plumbing during installation last year. I've discovered that there is no easy way to open up the filter unless I cut the pipe. Has anyone come up with a solution for easy removal of the top of the filter with the PVC piping?
Thanks in advance for reading, and for the feedback!
