Ok to use old bleach?

[Deb04]

We had our pool opened yesterday, so in the middle of shocking the heck out of it. Water is very cloudy, but improving.

I used up all of the Cal-Hypo I had in the garage, so I went out to the shed to get some more. Low and behold, there were 3 bottles of 12.5% bleach out there. They've been in the shed since last summer and have gone through the wild temp variations of a NH winter. I know that the strength is probably decreased, but is there any problem in using it anyway? I'm checking the FC every hour or two anyway, so if the strength isn't there i will be able to see it and add more chlorine from other sources.

Thanks.

 

[linen]

Most likely it is much lower than 12.5% by now. It should not hurt to use it though.

 

[Bama Rambler]

It won't hurt a thing to use it. As Linen said, it's probably not 12.5% but it'll still have some chlorine in it and may be more than you think.

I'd dump a known amount (maybe a gallon) in there and test it after a few minutes to see how much it upped the FC. Then you can use the pool calc to figure how much you need to add each time by changing the %bleach in the % cell.