Any reason why chlorine might disappear very fast? (no sun)

[zaboomafoozarg]

I've been trying to balance my 22k gallon pool (been sitting covered for 2 years), and have a strange situation. Chlorine appears to disappear very fast. A few days ago, I used 8 bags of super shock and the cl level tested 0 the next morning. So tonight I shocked it again - 4 gallons of liquid chlorine, and 2 hours later I expected a cl level above 10 but it tested as 1!

pH is still pretty high, looks like 8.5 or so, will get some more pH decreaser to get that down tomorrow. so pH is ~8.5, CYA is ~50, alkalinity is ~80.

There does appear to be a bunch of algae though - water tint is quite noticeably green. Has been swept/brushed.

 

[jblizzle]

Re: Any reason why chlorine might disappear very fast? (no s

What is your CC?

 

[zaboomafoozarg]

Re: Any reason why chlorine might disappear very fast? (no s

CC level appears to be the same as FC level, about 1-1.5. Did a test and the CC level was supposed to be the color after 10 seconds, and CC after 2 minutes. It quickly turned pale yellow and stayed that color the whole time w/ no change.

 

[duraleigh]

Re: Any reason why chlorine might disappear very fast? (no s

The easy answer is it sounds like ammonia which can form under some circumstances but always seems to involve a neglected pool.

If it is, you are going to burn through a ton of chlorine to eradicate it. There really is no other choice unless you can drain and refill cheaper.

It's still just a guess because the numbers you are posting are simply not reliable, You should get a good kit so you can figure out where your chemistry really is.

read "How to Shock Your Pool" up in Pool School