Chlorine Not Showing Up...

[tommypenngotti]

so for an 18k gallon pool , I was guessing 4-5 gallons of 10% bleach to shock? also is it normal to pour in a gallon & have a 0 FC reading instantly, eats it that fast?

*** ok , now showing 3-4PPM after 4 gallons ....just added another gallon .....where's the cheap bleach! $7 + tax for 2 gallons @ Leslie's

also the CYA stabalizer I added a year or 2 ago seems to have disappeared! thought that stuff was hard to get rid of & I'm using pucks as well! thx

[Watermom]

Some of us, me included, typically open to a pool with no CYA. I usually have a reading of 40 or so when I close the pool and usually find that I have none in the spring even though I open to clear water. Who knows. At any rate, it happens to several of us and is no big deal.

Glad to have you back around the forum this spring! Boy is it good to use that word. SPRING!!! I have been waiting impatiently for spring and SO glad it is finally here! Our flowering trees, forsythia and crocuses are blooming and the grass is growing. Life is good!

[chem geek]

This is a known and understood phenomenon that I write about in this thread at Trouble Free Pool under the sub-section "CYA Degradation by Bacteria". Basically, soil bacteria that get into a pool with no chlorine grow and consume the CYA turning every 10 ppm CYA into 3 ppm ammonia. This takes about 24-30 ppm FC to get rid of so looks like an insatiable demand for chlorine. In practice, some of the ammonia disperses (perhaps outgasses) or is taken up by algae so the chlorine demand isn't as large as predicted, but it can still be quite large.

You can buy an ammonia test kit from a pet/fish/aquarium store to determine more precisely how much chlorine it will take -- just multiply the ammonia measurement by around 8 to get the amount of chlorine it will take (it can be up to a factor of 10, but 8 is probably a minimum). Of course, if you don't want to test the ammonia level, you can just add chlorine until it starts to hold an FC reading.

Richard

[tommypenngotti]

thx guys - after Janet's advice - threw in 4 gallons of 10% & CL started registering/pool is noticeably clearer & added stabalizer & now I have a good healthy 4-5ppm reading & it stays .....we'll see about the CYA level once t all dissolves in & the sun hits it this SPRING!! thx !
tp