White Water Mold. Please help me get rid of it.

[ccshoe]

I think I have white water mold.......help me get rid of it! Let's start with the facts. 16,000 gallon salt water pool--however salt chlorinator is not turned on yet because I need to add salt and warm up the water. The other day I noticed the white tissue paper stuff in the pool. Called pool guy and he said to majorly, majorly shock the pool. Per his recommendation I added 20 gallons of liquid chlorine. Used my Taylor test kit tonight and here are my readings. TA 190, Ph 7.2, Chlorine no reading (this was using the color match test) Salt 2200, and for the Cyanuric Acid I could not get the black dot to disappear even when I filled it completely full. So I have added cyanuric acid and went ahead and added two bags of salt. Now what? Not sure what my next step is other than to test cyanuric acid tomorrow and see if it is up. How much more chlorine should I add? I did not add any because I thought it might be a waist since the cyanuric acid was so low. Also, would you recommend adding a flock / drop down and vacuuming to waist? Do I need to do anything to the filter? Pool currently looks pretty clear and shows little evidence of the white water mold, mostly just around the skimmer basket. The other day it was on the walls and we brushed it off before we super shocked. The bottom of the pool does have a lot of dirt like looking stuff on it that was not there the other day. Thank you, thank you for your help!

[chem geek]

Read Shock Your Pool. You got the white water mold because the FC level was not maintained high enough relative to the CYA level.

As for the chlorine reading, it sounds like you are using a DPD chlorine test, the kind that turns pink/red that you match against a comparator tube, and that can bleach out at high chlorine levels. Use an OTO chlorine test or a FAS-DPD chlorine test to confirm that you have chlorine. The FAS-DPD chlorine test is best and found in the Taylor K-2006 or the TF-100 test kits or you can get it separately as well (here or here) since you've already got a Taylor kit.

[Guest]

Did the other chlorine test and it was 0. Now what?

[chem geek]

If the chlorine level is truly 0, then you add chlorine to shock the pool (preferably chlorinating liquid or bleach, but you can use Cal-Hypo if your CH is low), but that isn't a one-time dose. Shocking is a process where you maintain a high chlorine level. You maintain shock level, which is an FC that is around 40% of the CYA level, until you pass the overnight chlorine loss test where you lose <= 1 ppm FC overnight and measure <= 0.5 ppm CC and the pool water is clear. Read the Shock Your Pool link I gave for more details.