At the request of another forum member I'm posting a new thread.
Last year I had what I'm pretty sure was mustard Algae. I discovered this at the end of last season, trusted the pool store (bad move I know), added some Yellow Treat algaecide (89% sodium bromine), and proceeded to turn my pool into a bromine pool that wouldn't hold chlorine. After quite a few bags of shock, i was holding 'some' chlorine as the cover went over the pool. I was not running the filter 24/7 prior, I was simply following what the pool store told me to do (bad move, again I know).
Fast forward to opening the pool this year. I have a mesh cover that blocks ~95% of the sun, but I still opened up to a murky mess. Perhaps that's the way it always is, perhaps my chlorine ran down super fast under the cover since I was just getting to the point where my bromine pool would hold 'some' chlorine. Maybe it was something else entirely, who knows?
So I slammed the pool for 1.5 weeks, everything looked good, and I started to let my chlorine drift downwards. At CYA 70 it never got below 7.5 ppm. Before I went on vacation I saw this uniform cloudy yellowish dust on the floor; given how heavy the wind was blowing and it being JUST out of the crazy pollen time of Spring, I chalked it up to pollen. Vacuumed it to the filter (didn't use the robot) [bad move in retrospect sending it to the filter, but again I thought it was pollen], verified my TC/FC, and went on vacation for a week.
I came home to a murky mess with yellow/green 'smears' all over the floors and walls. Now, given the pollen like behavior of the dust on the floor and my now cloudy smeared mess, I figured I had mustard algae. Interestingly, I still had 5 ppm of chlorine and no CC w/ CYA 70.
So I slammed for another week, passed my OCLT, brought my chlorine up to mustard shock, dumped all my toys, tools, testing tubes, etc. in the pool, and let it rip for 24-30 hours. I even put the robot (lovingly called 'Oscar' at my home) in and let him run around the super chlorinated water for 4 hours.
After that fiasco, i decided to dose my pool w/ Polyquat 60. I know, I know its not vogue around here but since the downsides save chlorine consumption at the beginning are only to my wallet, I choose the extra protection. The season is short here in the NE and slamming a pool really cuts into things. The dosage (after startup) calls for 2-4 oz per 10000 gallons every 5-7 days. I put in 9 ounces every 5 days. I add it in the AM through the skimmer w/ my filter on recirculate and the SWG off. I let it spin out there for 1/2 hour or so, than I go back and put everything back to normal for the scheduled run time. When I come home, I add 1 gallon of bleach around the perimeter to counteract the Polyquat 60 / chlorine drop.
*Have I mentioned that I am ON this thing?*
So - I've had my chlorine up to between 8.5-12 with a CYA of 70-80 since than. My CYA drifted a bit b/c for a time we had some 'Forest Gump in Vietnam' type rain here and i had to keep pumping the pool out. The first two times I backwashed, the last time I just sent it to waste. My low chlorine readings were always around my adding Polyquat, so I know that while it might have been lower than I would have preferred for a short time there was plenty of algaecide floating around in there at the same time. Also, even though my chlorine dropped it was still comfortably above my target for the CYA level I've had.
Now, along my seams, I sometimes see stuff that looks like what another fellow member posted: http://s1067.photobucket.com/user/Gi...mer/slideshow/
Mine looks just like this, but only appears along some seams on the floor of my pool. Never in the middle or in 'clumps' like she has. Just the seam. And only some, not all. Like, a small section of maybe 2 of them. Couple feet long, tops.
I have a free-form/irregular shaped pool and I often reflect how I should have chosen a standard shape as I'm convinced I have 'dead zones' in some of the curves. At the suggestion of yet another forum member, I have JUST changed my eyeball/returns 180 degrees to create a counterclockwise flow instead of a clockwise flow. Perhaps I'll get better circulation spinning the other way.
The algae in my seems, as pictured above but only along the seams, does not go away with me sorta whooshing the brush over the seam. It requires the brush to make contact and a few back and forths. So I don't think in retrospect its Mustard algae; also Duraleigh didn't think so either from the pictures I'm referencing.
So - here I am. I really don't want to SLAM a 3rd time this year, and I've been diligent with my chems; often erring on the high side of the chlorine just because I can. My SWG is set to 55%, and I run my filter 9 hours a day.
Water temp 87 (heater has been turned off)
The pool is crystal clear. What's my deal?