pH too high, TA too high, Hardness too low?

[happylioness]

We just bought a house with an in-ground pool with a vinyl liner. We installed a salt system when we had the pool opened a couple of weeks ago. I have been having the water tested by our pool company almost daily and adding the chemicals recommended to no avail. There has been very little (if any) change in the readings.
Today's reading is:

CYA = 46
Total Chlorine = 5
Free Chlorine = 0
pH = 8
Total Alkalinity = 235
Hardness = 95

Over the past week I have added ph Minus (5 lbs.), 15 lbs. of hardness treatment, and 16 lbs. of shock. My water is still a murky green. I can finally see the bottom in the shallow end, but not the deep. Yesterday they had me do a floc and clear treatment, assuring me that this morning my water would be clear and I could vacuum to waste the algae on the bottom. No such luck. I followed the instructions precisely, but the floor of my pool was mostly clean and my water is still green. I have vacuummed to waste, kept my filter(sand) backwashed, my chlorine generator is reading 3300 and I still have no free chlorine. Just now I have added 8 more pounds of shock. Can anyone tell me how to get rid of the green water. My pool bottom is clean.

[muss08]

What kind of shock are you using? What is the active ingredient? You need to get your pH and TA down and you need to get your own test kit. I use the Taylor K 2006. Most test kits dont test for pH higher than 8 so yours could be higher. Chlorine is very ineffective above 7.8. You need to add acid to get your pH down to about 7.0-7.2 then aerate the water to get your pH back up to about 7.8 and repeat the process until your TA is around 80ppm. Another concern is the fact that you have a combined chlorine of 5ppm which is very high. Combined chlorine plus free chlorine equals total chlorine. Shock your pool with a non stabalized shock to get your FC to around 20ppm and keep it at 20 until the level holds overnight. You can use granular shock- just make sure you dissolve it first in a bucket of water or use regular unscented clorox. Make sure to brush daily and backwash when needed. I wouldnt bother running your salt system until the water clears up.

[muss08]

Oh yeah- since it is a vinyl lined pool the CH is only a bit low. I'd focus first on getting your pH down and FC up.

[Guest]

Thank you for your help. I have been using SunBurn Extra Shock treatment, it is calcium hypochloride. Is this a good shock? My pool is a little clearer today. I put 2 gallons of muriatic acid in it this afternoon. My pH has come down some but my TA is still high. I still have 0 FC. I have turned my salt generator off for the time being. If you have any more suggestions I would appreciate it. Thanks.

[muss08]

Yes, cal hypo is a good shock because it is unstabalized which makes it more effective. If your FC is 0 you need to keep shocking. Have you had a chance to get your own test kit or order one? I cant stress enough how important this is. If you dont get a Taylor K 2006 just make sure the chlorine test is a FAS-DPD (very accurate-can test to .2ppm and can test high levels of FC) test and that the kit tests for pH, TA, CH, and CYA. What are your current readings? The muriatic acid will lower the pH much faster than the TA. This is why you must lower your pH to about 7.2 then get it backup through aeration so you can add more acid to lower the pH. If you keep adding acid until the TA is normal then your pH will be dangerously low. A good method to raise the pH is using your SWG. When this is generating chlorine it releases alot of bubbles which raises the pH. But I would wait to do all of this once your water clears. Just make sure you get your FC higher.

[Mars]

Sounds like you have been invaded by little green mites from planet mother nature…….. all u have to do is give it a strong dose of Algae-Plus 32 oz per 10,000 gallons then wait 2 days.

Thanks… The Mars Candy Company