Chlorine Not Showing Up...

[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