Where is the Chlorine going?

[nrshapiro]

My pool is balanced except maybe the Cyanuric acid, which is a little low. BUT: my chlorine levels remain low...in fact, I have 3 Slo Poke tabs in a floater, 2 in the feeder, and one in the skimmer. Still my chlorine levels remain low to nil.

So today, I put 2 gallons of liquid shock in my 25,000 gallon pool, and I just checked the Chlorine, and it's still NIL!

Where is my chlorine going?

Thanks...Neil

[PoolDoc]

My pool is balanced except maybe the Cyanuric acid, which is a little low.

Sounds like you may have answered your own question.

Add 2 gallons of bleach in the evening (within 2 hours of sunset) -- about 4 ppm of chlorine. Test in the morning within 2 hours of sunrise, then again that evening. If the AM chlorine is 4 ppm or above, and the PM chlorine is low, the problem is either stabilizer OR you used a bromine based product. (Anything from United Chemical; granular chlorine boosters for algae from other companies.) If the chlorine is low in the AM, then you have some sort of chlorine 'demand', from early algae, or pool goop you've added, or ??

If you want to be sure, post test results: chlorine, pH, stabilizer AND recent history of what you've added to the pool.