Question about CH Test Coloration

[jmarcum]

As far as the pH goes my test before adding the borax was 7.0. The calculator said to add 67 ounces so I did. Two hours later the reading was so dark that I'd say it's over 8.0.

On the calcium test it took me a little while to figure out what you meant when you said "old reagents" I bought this kit during the winter but I did leave it ouside all winter. I didn't know I wasn't supposed to do that until recently. This is the color "red" that I get...

[jmarcum]

I know the lighting is terrible in my house but this is the color after 40 drops...

[CarlD]

pH: With almost all chemicals we always say NEVER ADD THE FULL AMOUNT! Add 1/2 of the "recommended" amount, wait a couple of hours and test again. Gradual adjustment is the key. i don't use the pool calculator for just that reason--too easy to overshoot your goal. It works best for bleach, IMHO.

Now you need to add acid to your pool to bring pH down. I don't know how big your pool is so I would start with a cup of Muriatic acid. You can use Dry Acid instead. Either way, add it to a five gallon bucket of water FIRST before adding it to your pool. Do no breath the acid fumes...you will see vapor rise from the jug. Keep it away from your face and skin and wear safety goggles and gloves. Always add the acid to water, not the other way around!

Then pour the bucket into the pool's return stream and keep your pump on. Test pH in an hour and if it is still high repeat. 7.6 is ideal but any result from 7.3 to 7.7 I would leave alone.

CH: the colors look fine to me. 40 drops means a CH of 400ppm and you do not want to exceed that in any pool or you may face clouding or scaling. See if your pool store tester confirms that number.
However, I would go on line and order replacement reagents (testing chems) just to be sure. Always store them in a cool, dry place, indoors.

So, what is the ONE additive I don't mind overshooting on? Chlorine, of course!

[jmarcum]

Thanks again. I'll give the acid a try. From testing this am it took 4 drops to get the color down to the recommended ph. According to the ph chart that means I need a little over a quart so I'll just do a little at a time and retest. As far as the pool size goes the pool builder told me 12,000 gallons but the next time I refill it I'm going to get the water company to do before and after readings to confirm. Are any of the digital water testing devices available to consumers worth buying?

[CarlD]

I never bother with the acid demand test. My pH is too high? I add a cup of acid and recheck in an hour.

Pool volume is simple solid geometry. Once you have the cubic footage volume of the water, not the pool, you multiply by 7.48 to get gallons.

[jmarcum]

Now I am just totally confused. I did as you suggested, added small amounts of acid, retested 1 hour later. My test shows great numbers on everything so I took a sample to the pool store to see how right or wrong I was.

My Numbers:
FC:12.5
pH: 7.4
TA: 80
CH:400
CYA:70

The numbers and reccomendations from the pool store are below. She suggested I turn my chlorinator back on and set it to the Max (5) because, according to her test my FC is 0

[jmarcum]

Here's another quick test I did with a 6 way test strip. I know these are not as accurate as the Taylor but still this doesn't indicate anywhere near the 0 that the pool store reported.