Some of you followed my other thread where I got the pool clear. It was neglected for 3 years. During this process I accidentally shot the CYA way way high. (It WAS reading 0 ) Now I was told a couple things:
A: I need a better test kit to check chlorine - check - got duraleigh's FAS-DPD kit for chlorine. All other tests of walmart or Taylor K-2005C should be fine.
B: Only 2 things consume chlorine - organics and sunlight.
Well I went through the pool and took out every single little leaf, emptied the skimmer basket, etc. No apparent algae anywhere, water is clear and sparkling. AND it's dark outside.
Every time I test the pool it seems to be around .5 - 1 FC. 1-3 CC. No matter what I do, no matter how much bleach I add or how hard I shocked it. I'm preparing for a huge push on saturday bringing it to 25 and keeping bringing it to 25 (using probably 30+ jugs)...
CYA 100 (maybe slightly more, not much)
no metals, etc
17k-18k gallons, maybe less due to curved bottom.
So I add 2 jugs bleach. This should bring FC to 10. Now if there's algae blooming it's nascent at best. With my CYA so high the oxidation should happen more slowly and my FC should definitely come up. It's well after dark too. I leave for an hour and come home and use the kit. Same exact levels. This is with the pump running with main drain too.
HOW IS THIS POSSIBLE!? This happened the whole time I was shocking. The only way I finally managed to clear the pool was by adding 5 jugs bleach followed by 8 cups of trichlor which should have raised my FC to 48 ish. You'd think if I tested recently after adding that I would have a lot of chlorine reading but I didn't. I managed to clear the pool but I don't know how. *EVERY* time I tested, even an hour later I read .5 FC max.
The average uneducated person wouldn't worry but I need to understand what's happening here. Anyone have any ideas? The water temp is pretty cold, if algae is growing it's happening *really* slowly and showing *no* evidence.
I've tried adding bleach in front of hte returns or directly into the skimmer. No real difference in readings. I test by taking the leslies sample bottle, picking up water from 1.5ft down half-way between the 2 skimmers (kind of dead middle of the pool area). I get the water, bring it inside and test right away. Natural light isn't necessary for the FAS-DPD but even using my kitchen flourescent lights I can get relatively close numbers.
Please don't tell me to read the stickies, etc etc etc. I've read them... all of them. I've done my best to educate myself so if I'm doing something wrong, I need it specifically pointed out to me
I'm OK with buying 30 jugs of bleach at walmart despite the cashiers wondering what the heck I'm up to (I actually got laughed at by some teenager when I had a cart with 4 boxes of borax and the pool test kit) but I have to understand what I'm doing this for and if I'll succeed and what it will take to succeed. There MUST be a limit to this.
I'm really feeling the walmart 6% is either old stock wiht no potency or fraudulent.
Tonight I'm probably going to go get walmart bleach and test it in controlled conditions to see if I get the FC rise I think I should.