Bleach not staying in pool?

[waterbear]

Me: "Evan, So it's probably not bromine, right? It would be showing up on the tests at a much higher level if it was there, wouldn't it? (Excuse my ignorance if I'm misreading your post.)"
Waterbear: "Not unless the tester is also calibrated for bromine readings and you use that scale!"

Me again: I was under the (perhaps mistaken) impression that with the Tayor DPD test you couldn't really tell if you had chlorine, bromine, or a combination of the two. Further, that you only multiplied by the bromine factor (2.25) when you knew you had bromine sanitized water; otherwise you just assume it's chlorine. Am I way off here?

The taylor comparators have separate scales on them for bromine and chlorine and the taylor FAS-DPD test uses a different reagent (I assume it's the concentration that is different) for bromine and chlorine to take this into account. The actual test will not tell you which is in the water. You need to know so you know what scale to read or what correction factor you need to get the reading. As far as my understanding goes, if you have ANY active bromine in the water you have a bromine pool.

[KurtV]

Evan, Just before reading your latest, I went to Taylor's website and read through the instructions for the K-2005 and K-2006 kits; boy was I off base. Should have done that research before posting on this sub-topic.

I know that sometime in the not-too-distant past, I read something along the lines of what I posted but I must have misinterpreted it (or mis-remembered or mis-somethinged).

I think I have it now (at least to the limits of my meager intellect and too-long-ago chemistry education). Thanks.

[PhantomAndy]

Anytime I get any kind of algae problem that 10-15ppm of Cl doesn't permanently fix - I just toss a quart of Polyquat in the pool.

The past two years - I have had a 'whispy green' algae that starts to form right in the middle of the year. Shocking never gets rid of it - nor does vacuuming. The polyquat does the trick everytime.

Granted - it's a little expensive @ $20+ a quart - but worth it in terms of time saved.

[h20man]

I checked my CYA & it was @ 7!! Didn't think just warm water can eat up CL as fast as it's been going...pool is @ 85 deg.
FC 0.1
TC 0.2
CC 0.1
PH 7.3
CYA 7
TA 178 - high
CALC 385 - high

dumped in stabalizer & re bleached tonight w/ 2 gallons 10% , we'll see tomorrow

my next question is w/ my ALK & CALC being so high , how can I add muriatic acid w/o dropping my PH too low, maybe I should stay put?
thanks

[KurtV]

H2O,

Your alkalinity is high but not crazy high and your CH is in the acceptable range (at least according to most of those "recommended levels" tables you see). I wouldn't worry about either for now.

Something is still eating your chlorine and really, no matter what it is, the cheapest and most effective recipe for fixing it is probably more chlorine. Dose up the chlorine to shock level as you're doing (10 or 15 ppm will probably work with your low CYA level), test frequently (like 3 times a day if you can), and keep adding chlorine as needed to bring it back up to your shock level. Once it holds free chlorine overnight you should be on the downhill side of this.

Good luck.