Puzzled about no FC

[tundraSQ]

I am kind of reaching here...so you might do a search....I believe I have read that with some tests, it is possible to have SO much FC as to register as ZERO....anyone else read that here?

[waterbear]

some strips will bleach out with high chlorine....depends on the reagent that they use.l

[LearningCurve]

some strips will bleach out with high chlorine....depends on the reagent that they use.l

I was attempting to rule this out by diluting the sample with tap water. I started 1/3 pool to 2/3 tap water, and the strip tested no FC. I actually did it again 1/4 to 3/4 and still got none.

[waterbear]

When you closed the pool was your CYA level higher than the 30 ppm you tested now? If so it is possible that some of your CYA biodegraded. This would cause a huge chlorine demand since the bacteria will excrete ammonia compounds and urea.

[LearningCurve]

When you closed the pool was your CYA level higher than the 30 ppm you tested now? If so it is possible that some of your CYA biodegraded. This would cause a huge chlorine demand since the bacteria will excrete ammonia compounds and urea.

I know that the CYA was arount 40 when the pool was closed last year. The bill from my dealer has 4# of "conditioner" So I assume that they put CYA in also. So my best guess is that there wasn't much left at open.

If this is the case, how much chlorine would a guy need to put in to overcome, and still not damage the liner?

THANKS!

[aylad]

Check the Best Guess chart sticky note at the top of the chlorine forum...

Janet

[LearningCurve]

Check the Best Guess chart sticky note at the top of the chlorine forum...

Janet

I don't think you understood my question.
I realize that the best guess sticky has 15ppm as a shock level.
I have already put enough chlorine in that should have taken it beyond 15ppm.

This would cause a huge chlorine demand since the bacteria will excrete ammonia compounds and urea.

How much should this take to overcome this ammonia compounds and urea ?
At this point I am assuming I have a WHOLE BUNCH of CC.
IS CC bad for the vinyl liner?

I appreciate the help!