Test results and gypsy moth doodoo

mm3846 · Jun 20, 2017

hey all. been doing a lot of cleaning and putting the dolphin vac on overtime but my pool is finally clear save for the caterpillar poop everyday and half eaten leaves coming down. I've seen enough of that in the past couple weeks to know I can't do it again so I'm chopping a couple trees down that hang over the pool in the next few days. I got sprayed twice but I never saw results from that. Anyway, I got the taylor kit and did a reading.

FC 2.2
CC .4
PH 7.4
TA 250
CH 120
CYA 90

CSI -.85

I did add a little bit of stabilizer before I got the taylor kit and listened to the pool store, but only added 3/4 of what they recommended. I did the SLAM for 2 days, but due to a work trip (and all the caterpillar poop) I don't think I was keeping up and haven't done a OCLT yet, I'll run one tonight. What's my best course of action here? Pretty sure the poop is eating up all my FC, I'm running my filter 4.5 hours a day from 230-630, dolphin goes in around 330-4 when I get home and does a full cycle. Pool is clean before dinner but a mess again in the AM.

Razorhog · Jun 20, 2017

Your FC is way too low for your CYA level. Step one would be to drain a lot of the water to get your stabilizer (CYA) levels down. With FC levels that low and CYA that high, caterpillar poop is not your only worry. Algae is probably already growing.

FC / CYA chart: Pool School - Chlorine / CYA Chart

mm3846 · Jun 20, 2017

Also, I'm not sure if my CYA reading is accurate. I had a reading of 17 last week and added maybe 4 lbs? of CYA. I did put some trichlor tabs in before I went away but could all of that really bumped it that high? Pool is crystal clear otherwise.

Razorhog · Jun 20, 2017

mm3846 said:
Also, I'm not sure if my CYA reading is accurate. I had a reading of 17 last week and added maybe 4 lbs? of CYA. I did put some trichlor tabs in before I went away but could all of that really bumped it that high? Pool is crystal clear otherwise.

No - adding 4 lbs CYA would only raise it by 17 ppm in a pool that size. You can use pool math to figure this stuff out - https://www.troublefreepool.com/calc.html At the bottom there is a section that will tell you what the effects of adding anything will do. Be sure to enter in the size of the pool at the top. Anyway, the CYA in the water never goes away so you probably had some left over from last year.

mm3846 · Jun 20, 2017

Razorhog said:
No - adding 4 lbs CYA would only raise it by 17 ppm in a pool that size. You can use pool math to figure this stuff out - https://www.troublefreepool.com/calc.html At the bottom there is a section that will tell you what the effects of adding anything will do. Be sure to enter in the size of the pool at the top. Anyway, the CYA in the water never goes away so you probably had some left over from last year. Do you have a test kit?

Yes, the taylor k-2006 fas-dpd. Its possible I was just staring at that dot too long.

Razorhog · Jun 20, 2017

mm3846 said:
Yes, the taylor k-2006 fas-dpd. Its possible I was just staring at that dot too long.

Yeah the CYA test is the weak link in pool testing but you can get good estimates using it with practice. When you read the test have the tube waist high and your back to the sun. If you are not sure or want to try it again, just pour the water back in the mixing bottle and start over so you don't waste reagents. I also recommend using the 10ml water sample size for FC because it uses less reagent and you'll be using a lot of it very soon for the SLAM.

mm3846 · Jun 20, 2017

Righto. I'll check it again when I get home. If the CYA is at a more normal level should I add bleach or whatever to up the FC to a normal level, then run a OCLT? Good plan?

Razorhog · Jun 20, 2017

mm3846 said:
Righto. I'll check it again when I get home. If the CYA is at a more normal level should I add bleach or whatever to up the FC to a normal level, then run a OCLT? Good plan?

Yes test CYA again and go from there. Bring FC up to your normal range and then do the OCLT. If CYA still tests at 90, you'll need to drain 33% of the water to get it down to 60. Sounds like you have a good handle on it, just report back and we'll help.

mm3846 · Jun 20, 2017

Razorhog said:
Yes test CYA again and go from there. Bring FC up to your normal range and then do the OCLT. If CYA still tests at 90, you'll need to drain 33% of the water to get it down to 60. Sounds like you have a good handle on it, just report back and we'll help.

Thanks. It seems pretty simple, especially with all the aids and calculators available online.