Unexpected low CYA

[themalldude]

Hi all -

I've been using BBB since we moved into our new house about 3 months ago. When we moved in, I ordered the TF100 kit and started manually dosing the pool with 8.25% bleach. When we moved in, CYA was in the 120 range and I did a couple of partial drain/refills to pull it down to 50-60. Since then, we've been on autopilot with daily additions of bleach and muriatic as needed, nothing else has been added to the pool except we've been doing a little pumice stone scrubbing to remove some scaling that was there when we moved in - no chemicals just elbow grease.

This morning I took a full set of readings as follows:

FC - 7
CC - 0
PH - 7.5
TA - 80
CH - 180
CYA - filled to the top and could still see the dot

I repeated the CYA test and had the same result. Any ideas on how my CYA could be zero?

We've had normal use this summer, and there is a drain at the top of the pool's normal water level (maybe some drain out as we top off the pool daily). But I wouldn't have thought the CYA could have gone down 50-60 points?

I was thinking about taking a sample to Leslie's in case I'm getting a bad reading (my test kit is about 4 months old now)....

Thanks for any input or ideas you have...

 

[spidey07]

Sounds like a leak. Do a bucket test to be sure.

 

[themalldude]

Thanks! We're losing about 1" per day but I just thought it was the heat of the summer doing it. Will check it out with the bucket test.

 

[duraleigh]

If you are truly losing 1" in a 24 hour period, no real need to do the bucket test....you have a leak. Total desert climate might be the exception.

 

[themalldude]

Thanks for the info Dave - that must be it.. Thanks again!