CYA keeps dropping

[bearclaw20]

I originally put this question in the wrong forum and I don't know how to delete so I moved it here....b/c I don't know how to delete it

Hi Guys-

I can't get my CYA to stay put...I thought I got it up to 40 then we had lots of bad storms and rain and had to backwash a lot of water out b/c it was about to top over- I tested and it had dropped to 30- so I added some more CYA (granular in a sock let it dissolve for a day, didn't backwash for a couple) wanted to get it back up to 40 (which I got it back to 40)

I keep losing a lot of chlorine (was 90 all last week and mid 80's this week) so I get that there will be lose of chlorine, but I just got my new test kit refills and tested today and it at 27-30...I am at a loss...in 9 years never had this issue or maybe I wasn't testing right and finally figured it out LOL....

Anyways we are going to be gone for several weeks and have someone keeping up with the pool...should I try to get CYA back up to 40- and then have our house/pool keeper top up the bleach every night with about 30 ounces? to keep chorine within range of 3-5? (they wont best testing bc they have NO clue)


Thanks in advance

 

[BoDarville]

Losing some CYA due to a series of significant rains/storms is not unusual. It's happened to me with all the rain we got this spring and, in particular, in mid-late May after I initially dosed up my CYA.

I keep losing a lot of chlorine (was 90 all last week and mid 80's this week) so I get that there will be lose of chlorine, but I just got my new test kit refills and tested today and it at 27-30...

I'm a bit confused here...are you saying that the chlorine level is at 27-30 or are you referring to the CYA level?

 

[bearclaw20]

oops sorry...I meant my CYA dropped from 40 to 27-30 tonight I just tested...


how much should my Chlorine be dropping as well? I top up to a 5 each evening and then after an entire day of swimming and hot sun it gets down to about a 2 is this normal?

I use the TF test kit as well and test for FC and have 0 for my CC

 

[BoDarville]

Based on my experience and what I have seen on the forum, losing about 30-40% per day is about the average chlorine loss at this time of year. It depends on several factors - how warm the water is, how much sunlight is hitting the pool, the bather load, etc. Those with pool covers will lose less chlorine vs. those who don't. If you are losing more than 40% per day, I would try an OCLT - Overnight FC Loss Test. This eliminates sunlight as a source of chlorine loss. If you fail the OCLT, it is a sign that there is something organic in the pool that is consuming chlorine (like algae). OTOH, if you pass the OCLT, but you are still losing more than 40% chlorine per day, then I would bump the CYA up a bit.