opening pool - water test results

[mike_311]

ok, so i took the first step of advice and got a water testing drop based kit. i got the taylor complete version.

Background: i had some serious issues last summer with algae and im starting it off right this year, so help me out, please

I live in NJ, i have an above ground pool and its a 12x24, right now the winter cover is still on, i plan to get the pump out of storage today and start opening the pool, i figure with the weather still cool, it will let me take my time to get the chemistry right before the kids rush me to start using it.

ok, so now the results:

PH - 7.4
Alkalinity - 180ppm as calcium carbonate
Calcium hardness 150ppm as calcium carbonate
Free chlorine - 0
Total Chlorine - 0
Cyanuric Acid - 100ppm, actually could be above that if that possible, the test didn't even make it to the 100 level, the black dot disappeared way before it.

so what are the next steps from this point? i still need to add about a 1ft of water to get it above the skimmer. I also tested my tap water and its PH 7.4.

Thanks

Mike

[PoolDoc]

Hi Mike;

1. Taylor "Complete" as in, K-2005 with DPD color match? If so, go to the testkit info page, and order a K-1515 DPD-FAS supplement. With your pool's high CYA, you will absolutely need it.

2. Collect a new water sample. In a glass mixing cup, add 1/4 cup of pool water, and then 1/4 cup tap water. Mix. Fill your CYA sample bottle with this mix to the first line. Add CYA reagent to the 2nd line. Do your CYA test again. Multiple result by 2. Yes, it's VERY possible you have a CYA level more than 100ppm.

3. Buy 4 gallons of plain 6% household bleach. Mix 1 with 3 gallons water (you don't have to mix it all at once -- if you spill this mix on your clothes, you'll need a new set of clothes!). Pour the mixture into the pool from at least 4 different locations.

4. Figure out how much it would cost to drain and refill with fresh water.

5. Post the CYA test result, and the estimated refill cost.

[mike_311]

1. i have the K-2006.

2. about 190ppm

3. what does this do, beside chlorinate my pool...?

4. that bad huh? about $100 to refill.

==============================
also which kit? the k1515a or c one is $15, one is $50...

[PoolDoc]

OK. 190 ppm CYA.

What that means is that you'll either have to drain the pool OR you will have to run a NORMAL level of chlorine 15 - 20 ppm.

Downsides:
- the ONLY way to test your chlorine is with the K-2006 (C model has 3x the test reagents -- get it, if you don't drain!)
- you'll need a $75 pH meter to test your pH (high chlorine screws up the pH test, though maybe not with CYA=200ppm.)
- dealing with algae will be a little tricky, and you'll need to keep a $20 bottle of sodium bromide on hand for that purpose
- if you have your water tested by a dealer, you'll get weird responses, ranging from head scratching (Not sure what's going on with your water) to panic and hyped up sales attempts (OMG! Drain today or die! And, buy $1,000 of our chemicals to help clean up!)

Upside:
+ chlorine usage will be VERY low.
+ you'll be able to dose chlorine 1x per week (go from 15 ppm to 20 ppm)
+ vacations will be easy (just dose to 25 - 30 ppm -- and take off. As long as the pump runs, and you're back within 10 days, you should be fine!)
+ your water chemistry will be VERY stable.
+ If you also use borax at 50+ ppm, you will have even MORE stable water chemistry, reduced chance of algae, and very high water quality

Your choice, though. If you drain, drain to 1/4 level, so you don't have to add stabilizer

The Best Guess page, linked in my sig, explains some of the chemistry and the options.

[mike_311]

trying to figure out how low to drain. what level of CYA am i shooting for?

[PoolDoc]

Well, based on your results, you should have a final level of about 50 ppm, if you drain your pool to the 3/4 empty point, and then refill. 50 ppm is a good level to use with bleach, if you want to operate conventionally.