Clear water but using way too much chlorine

[poolmama3]

I am new to TFP and really need some help. I am having trouble keeping my FC level up. I thought maybe it was an ammonia problem so even though I didn't have an ammonia test, I began slamming last weekend. I read and did everything recommended in pool school and kept my chlorine level at 20 for 1 1/2 days. After blowing through at least a dozen gallons of 9% liquid pool chlorine and seeing no results, I was disgusted and decided to let the level fall back down to a normal level. Purchased an ammonia test kit Monday and found that isn't the problem. Shocked it again last night just to see what would happen overnight and I dropped from 26 to 16 FC then dropped another 8 throughout the day today. Help!!

FC=8 1/2 (It was 26 last night before bed)
CC=1.5
TA=100
ph=7.2
CYA=50

 

[Texas Splash]

Hello poolmama and welcome to TFP! Chlorine loss is certainly important, and it's been hot the past couple weeks. Based on what you have stated, I would be inclined to recommend you continue your SLAM. I know it stinks, and is a lot of babysitting at first, but that's the only way to remove algae. A few things to consider:
- Even though your SLAM FC is 20, make sure it never drops below that at ANY time. If you need to take it up a couple ppms, that's fine, but don't let it drop
- Consider verifying your CYA one more time. If you record it as low, then you'll never be at the correct FC (which test kit are you using?)
- Did you keep the pump on 24/7, sweep and brush each day - multiple times if possible?
- CC of 1.5 indicates your pool is processing "trash" chlorine, so there's something going on; failed OCLT validates that as well
Sorry I don't have better news or any other simple solutions, but I feel the SLAM is what you need. Just stick with it and "Maintain". I hope you resolve your issue soon.

Again, welcome to TFP!

 

[pabeader]

You're obviously killing something. Might be hiding in the stairs or some other place like that. Also, algae is a very small bugger. You could be just on the edge of an outbreak and need to SLAM harder then most for some reason. SLAM isn't a one or two time thing. It's a continuous until it's done kinda thing. A clear pool is only one of the criteria. Low FC loss <1ppm and LOW CC under .5ppm are the others.