Helping neighbor with pool

[Watermom]

What CYA reading did you get? If you got 100, then it could actually be much higher than 100 since the test can't differentiate levels past that. The chart you are referring to is the Best Guess Chlorine Chart in my signature below.

Is this pool on well water or city water?

[PoolDoc]

OK. Watermom asked me to take a look. Please do the following:

1. Add borax 3 boxes at time (slowly, in the skimmer, pump running).
2. You know your CYA is high, and you know you've got slime, so look at the Best Guess chart: you need 25ppm of chlorine! For a 36,000 gallon pool, that's 16 gallons. BUT, we've got to get that pH up first, so add ONLY 12 gallons for now.
3. Get a gallon of distilled water (must say "distilled", not spring, not Ozonated, not natural: "distilled"!) at Walmart in the water section.
4. Begin testing pH with 1/2 pool water and 1/2 distilled water. (With distilled water, the pH will still be about the same) High chlorine can create bogus phenol red results.
5. AND, retest the CYA, with 1/2 pool water and 1/2 distilled. In this case, multiple the result X2.
6. Let us know if the green color is CLOUDY green (algae) or CLEAR green (alkalinity or sometimes iron).
7. As SOON as you have a valid pH greater than 7.2, add 2 MORE boxes of borax, and then enough chlorine to get to 25 ppm.

Good luck!

[jilted]

Thanks. Yes on the CYA test the dot was gone well before the 100 mark. Since they are still not home from work I went ahead and added 9 gallons of bleach that I went and picked up. So until I can get those results do you suggest dilution at all? It needs vacuuming so they can waste vac some water and we can add some fresh if you think that will help.

So far the water is clear green but you can see a little build up on the surface.

Challenge accepted!

[PoolDoc]

You need to find out what you are diluting with, before you dilute!

build up on the surface

-- what kind of build up??

[jilted]

looks like algae but i could be wrong.

[PoolDoc]

. . . better add more chlorine, and better get that CYA test done ASAP.

If the CYA is > 100 ppm, some forms of algae can continue to grow (once established) at 10 ppm of chlorine.

[jilted]

Right before (maybe an hour) they put 3 boxes of borax in.
Also, they did a little waste vacuuming this evening to get dirt out and that stirred things up so now we're green and just a little cloudy.

ok here's the 1/2 pool water and 1/2 distilled water tests:

pH: very close to 7 so let's just say 7. I am assuming this is a good thing? Finally getting close? :-)
Base demand: 5 drops to get to 7.4, 7 drops to get to 7.6
CYA: reading was 70, multiply by 2=140
I tested ALK with the 1/2 and 1/2 water and it tested 40 ppm just like earlier with only pool water.
Also tested FC with the 1/2 and 1/2 and it tested at 22ppm

Will test again in the morning. They wiped out the store of Borax again. I think they have 4 more boxes in inventory and 4 more jugs (6 gallons) of bleach.

thanks
-stephen