I APOLOGIZE FOR VERY LENGTHY POST. But at this point, I feel it's necessary to provide a little background on our situation in hopes that we can get some help (also have prior thread on this).
OK, so we'd had our pool for one month, with near perfect balanced water (although we hadn't started BBB yet - didn't know y'all existed!) and lots of kiddos swimming in it. THEN, we had 2 neighbor kids over, who've had MA problems in their own pool (and they swim in the lake all the time). The next day, we had these little "spots" of mustardy-colored sand here and there - not much of it. We didn't think anything of it and went our merry way for a couple of weeks. It seemed to multiply. I'd brush and vacuum (not to waste) and within an hour or two, it would be back..in the same spots pretty much (divets and crevice where happy bottom meets)!
So, after reading that MA can be transferred from swim suits, and knowing that our neighbor kiddos had MA troubles, we determined it was MA and went to a few pool places for help. We did the Yellow Out and Power Powder Plus (Leslie's) and the whole routine they gave us, along with LOTS of backwashing. We bought an in-ground manual vac head (without the bristles) and used it, because the bristles on the above-ground vac head kept dusting up the stuff and it wouldn't get vac'd. We finally got ALL of it vac'd out to waste, backwashed and sprayed the ladder (which had been removed) with full bleach! Turned the pump off for the night, for the first time in a couple of weeks. Got up the next morning with a CLEAN pool! Did a "rinse" on the filter before turning it back on, just in case anything was still in the pipe. Turned filter back on and a couple hours later, the stuff was right back on the bottom of the pool!
So we've been assuming all this time that it is mustard algae - ALSO, because we keep getting some Water Boatmen. (seems like they come and go, but we try to catch and kill them when we know they're in the water!) But now that I finally got a GOOD kit (TF-100) on Tueday, 8/5, we bought lots of Wal-Mart bleach in preparation for the KILL! Brought FC up to 7ppm and called it a night (I didn't verify the FC 7, but this is my standard routine now).
Wed, 8/6, I tested and was still FC 7. After discovering at 3:30 that I'd not turned on the pump, I rushed out and looked at the water. It was very still....WITH LOTS AND LOTS OF "STUFF" ON TOP OF IT! But the bottom had almost nothing on it! Only tiny remnants of the "sand" here and there. And this was after almost an entire day of the filter not running. I'm now thinking, pollen (given that our son's nose alerts us routinely!) So I turned the pump on and later that evening, added enough bleach for maintenance only - to bring us up to FC 7 (I bring us up to 7 each night in anticipation of a 2-3ppm drop during the following day). I have been keeping the pool brushed a couple of times each day. I verified my FC 7 before going to bed Wed evening - and let the pump run all night, since I'd missed nearly the whole day. Checked it again Thur, 8/7 at 6:30a.m., and it was STILL FC 7. While this is the 1st time I've ever done the "check it late P.M./early A.M." thing, it seems we don't lose FC during the night, whether we run the pump all night or not. I've never had CC, since I started the BBB method.
So could this only be pollen, that's been plagueing us since the first week of June, and NOT mustard algae? I started using the skimmer sock about 6 weeks ago and it's been great! I clean it each night when I service the pool. The "sand" it picks up doesn't seem to feel slimy. It seems if I vacuum a couple of times during the week, there's not very much of it - but it's still there. I never have a clean pool anymore.. I'm only vac'g once a week at this time (health reasons) and it seems there's a lot more of it - but not like a sheet or anything.
We have the bleach necessary for an MA kill. Should we go ahead and do it, just in case? After listening to 3 different pool stores (in the beginning), we already have a slighltly bleached liner, especially in the deep end.
For those who can make it through this long explanation, thanks and we'd appreciate your help/advice/opinion!!