OK I've had it with this pool already and its not even July yet. I appear to be having a problem with the mythical chlorine block/lock no matter how much shock I add within hours I always have a 0 reading for FAC and TAC.
We started out the year just fine and then just about 2 weeks ago started to have a problem with mustard/yellow algea. We purchased a product called Yellow Out and followed the directions given to us which was to add the Yellow Out wait 5 minutes and 3 bags of shock, 12 hours later add 3 more bags, 12 hours later add 3 more bags. So after all that the pool water is clear but chlorine levels are @ 0. I added 3 more bags Still @ 0, 3 more still @ 0.
Several days after adding the Yellow Out I had a yellow frothy substance that was floating around in the deep end of the pool. I'm assuming this is the dead yellow algea because before it wasn't floating it was on the bottom of the pool. Anyway I skimmed just about all of it out and as I see new pockets develop I'm skimming them out.
Yesterday a took a sample to the pool store they tested the water and said I had a Chlorine Block and that I needed to add 6# of shock. I added 8 to be on the safe side. I added it last night @ 10PM no sun to help burn it off, this morning before sunrise I tested it and it shows 0.
Here are the results from the pool store yesterday
This is an inground 18x36 pool aprox 25,000 gals salt water pool.
So in the last week I've added aprox 23 pounds of shock, while the whole time my chlorinator has been on super chlorinate, and I still show 0 FAC and 0 TAC. Personally I'm clueless as to what to do, and quite frankly I don't think the pool store people are any better.
Any advise would be greatly appreciated.