ok, so i'm new to this forum and this has been a "must read" and very enlightening for me. Here is my situation and members please guide me and let me know if you agree...
Last season battled yellow/green algae almost all season. My solution (dumb) was to add pool store chemicals and vacuum every other day. Bad, I know now! Fast forward to last week when I opened it and removed the cover. Green swamp. added 10 lbs dichlor based bagged shock, and put 3 hockey puck (trichlor) tabs in the auto chlorinator. vacuumed to waste and swept all algae to a clean looking pool. However, sand and silt like algae (mustard algae?) kept reappearing in the same place...shady side bottom of pool. kept adding 5lbs shock and vacuuming and mustard algae kept returning in 24 hours. Meanwhile, I am never able to get a good FC reading at the pool store and using my test strips above .5ppm. I have since ordered the 2006 test kit and await delivery! I suspect the algae is stealing all my shock and chlorine.
To confuse matters more, my CYA seems to be all over the map, from 189, to 42, to 106, to 62.....in 4 pool store water tests done in the last 9 days. I have drained about 20% of the pool and replaced the water. I also stopped the dichlor shock and temporarily replaced with cal-hypo....no better results
So, now I believe my best option is to treat for mustard alage. Agreed? Reading the forum instrux, I need to get to my shock level as dictated by my CYA level. How long do I keep it at shock level since I'll always fail the OCLT b/c of the mustard algae? At what point do I bring the pool to mustard algae shock level?
Some other pertinent details. I will now be shocking with 12% liquid bleach/shock and chlorinating with 8% bleach and converting to the BBB method. Aside from a couple of beach towel sized areas of what I believe is mustard algae, the pool is crystal clear.
sand and silt like algae brushes away easy but keeps reappearing in the same spot. Even after vacuuming to waste.
Most recent water test results from the pool store yesterday:
water temp is 66
SUGGESTIONS AND HELP APPRECIATED!