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Salvino
07-08-2013, 09:10 PM
Hi -
I am a first year pool owner - having bought a house with a 10-15 year old inground Chlorine pool.
I'm figuring things out but I have a recurring issue of when I shock with HTH Extra Shock (75% hypocalcium chloride) - I end up with a whitish cloudiness in pool which takes a few days to clear. Any idea why?

Pre-shock values:
Size: 70,000 L
Chlorine source: Hypocalcium chloride in form of HTH capsules in skimmer (stopped using tichlor to arrest the CYA build up)
Sand filter with heater
Free Chlorine - 2.92 (usually around 3-5ppm)
Total Chlorine - 3.51 (thus the need of shock)
Total alkalinity - 120ppm
Calcium Hardness - 170ppm
pH 7.6
CYA 44ppm (started at over 100 and dumped half the water and still trying to get rid of more with backwash and fresh water...)
Cu+2 - 0.3ppm (used to be over 1.0ppm due to heater fried previous year - wroked hard to get levels down)

SHOCK -
Brush sides of pool added 2 capfuls of Metal-free (to keep Cu+2 in solution)
1 bag of HTH Extra shock

CLOUDINESS - whitish

Thanks for any help

Connie

Chlorine went above 10ppm

PoolDoc
07-08-2013, 11:54 PM
I'm figuring things out but I have a recurring issue of when I shock with HTH Extra Shock (75% hypocalcium chloride)

"Hypocalcium chloride"? Is that really what is says of the label? If so, it's not shock.

However, if you add lots of calcium -- either as calcium hypochlorite ('shock') or calcium chloride (calcium or hardness 'increaser'), you will tend to leave a lot of precipitated calcium carbonate in the water.

If you are *already* using cal hypo pills in the skimmer, there's probably no reason not to add the cal hypo 'shock' via the skimmer as well. Doing so will tend to trap precipitated calcium on the filter, BEFORE it clouds your pool. Just make sure to run the pump for at least 1 hour after shocking in this manner.

OTHERWISE . . . just use plain 8.25% household bleach. On your pool, one gallon will add about 4 ppm of chlorine to your pool.

Salvino
07-11-2013, 07:56 PM
hee hee - yes Calcium hypochloride it is

got it - will give it a try and see

won't adding shock to the skimmer and going directly into sand filter damage anything - pipes, filter, heater?

connie

Watermom
07-12-2013, 06:34 PM
No. Many people routinely add their bleach directly to the skimmer including me. Just pour it slowly while the pump is running being careful not to splash it on yourself.

Salvino
07-13-2013, 02:56 AM
Thank you

I noticed on the bottom of your reply another thread with this information (perhaps you had added it) in reply to a question about TA levels....

"Otherwise, it's not a problem, except that your pool will be 'twitchy' with respect to calcium and pH. If you add a shock dose of calcium hypochlorite, you might cloud your pool badly. Likewise, if there's much calcium in your pool, letting the pH go up a bit could result in a very cloudy pool."

Prior to posting I had been suspecting PH as a potential contibutor to my cloudiness after shocking....my PH does tend to run high 7.6-7.8 due to the maintenance Calcium HypoChlorite capsules that I use (they are ~PH 12) - so I am fairly regularly PH downing my pool. I had noticed that after shocking with HTH Extra Shock that indeed my PH goes fairly high up and then the next day I pH it down but by then the white precipitate is present. Can I PH DOWN just before shocking to stop the bounce and hopefullyy avoid the precipitate?

Connie