New to the neighborhood - kinda hopeless pool problem

[BSpade]

So I've been reading about TFPC and BBB but not having much luck getting the numbers to be what they should be.

The local Ace Hardware store has just started doing pool testing, so I thought I would see if they could do better than I have been able to. Here are their results:
FC: 1.2 ppm
TC: 1.8 ppm
CC: 0.6 ppm
PH: 6.4
Hardness: 27 ppm
Alkalinity: 0 ppm
CYA Over 158 ppm

Their recommendation is to drain 62% of the water and replace, but due to the current drought / water rationing in the area, refilling is out of the question.

Is there anything I can do other than dig out my radio controlled boat? At the moment the water is clear, and it sure feels good to sit in (current temprature is 114 degrees).

Help???

 

[Richard320]

Welcome!

It appears you have been feeding that pool a steady diet of trichlor pucks, hence the elevated CYA levels and the low pH and alkalinity. Trichlor is very acidic. That water is probably irritating to eyes if not skin with that pH and could very well be etching the metal innards of your heater. That is, if those results are accurate.

If the pool isn't green, it CAN be maintained with that high CYA level. I've done it. It's not easy, and I don;t recommend it, but it is possible. The key is to maintain adequate FC for your CYA level.

If the CYA is 160, you need to maintain FC above 12 at all times, and generally dose it to 15 or 16 every day. Using bleach. Using trichlor or dichlor will just aggravate the situation. And I don't trust that CH reading at all, unless the pool water runs through a water softener.

Step one: order a proper test kit. There are only two on the market that can measure the FC levels you'll need to maintain. The best value for you is the TF100 with the XL option. You'll be using a lot of the FAS-DPD powder, which is nearly impossible to find in stores.

Step two: raise TA to about 60 using Baking Soda. Walmart sells it cheap in big bags. This pool school article will tell you how to use poolmath to calculate doses.

Step three: thirty minutes after adding Baking Soda, raise pH using Soda Ash - Washing Soda - pH increaser leftovers. They're the same stuff. What chemicals do what and how to add them are here.

Once TA is somewhere north of 60 and pH is between 7.2 and 7.8, add bleach to get FC up to about 16. You may decide you need to target higher or lower to keep FC from dipping below 12.

The pool store will get excited and tell you that 12 is too high. Ignore them. It's marginal for your CYA level. I've swum in water with 24 FC with no problem because of the buffering effect of 220 CYA.

It may be possible to chlorinate with Cal-hypo powdered Chlorine, but you need to be absolutely certain of your CH level via your own testing before you exchange one problem for another. No more Dichlor or Trichlor for you.

 

[jmbradwell]

+1 on Richards comments. One thing you can do is turn off your lawn irrigation and irrigate using pool water. It's a slow process, but it will help to lower your CYA.

 

[BSpade]

Hi Richard, thanks for the quick reply.

You say:
Step one: order a proper test kit. There are only two on the market that can measure the FC levels you'll need to maintain. The best value for you is the TF100 with the XL option.
I just got the HTH 6-way test kit (It was mentioned more or less favorably on another forum) so I doubt that I can get a $80+ purchase past management. Would the FAS/DPD Chlorine & CC's test kit by itself give me what I need?

You say:

Step two: raise TA to about 60 using Baking Soda.
I've been dumping Baking Soda into the pool for about a week now, tests still show TA = 0. Is this an effect of the CYA overload, or is there something else going on?

You say:
Step three: thirty minutes after adding Baking Soda, raise pH...
Is this worth doing if TA is still low?

You say:
Once TA is somewhere north of 60 and pH is between 7.2 and 7.8, add bleach to get FC up to about 16.
and:
No more Dichlor or Trichlor for you.
Right. It does seem reasonable to increase FC by adding a few jugs of chlorine bleach.

Thanks again for the help.

- - - Updated - - -

+1 on Richards comments. One thing you can do is turn off your lawn irrigation and irrigate using pool water. It's a slow process, but it will help to lower your CYA.

Due to our drought, the lawn hasn't been watered for months. What happens if I use the pool water on fruit trees? Do I get peaches that smell like chlorine?

 

[Richard320]

I would question the test kit if it never reads TA.

Yes, the FAS-DPD standalone kit should fill in the blanks.

You definitely need to get pH up. That's got to be rough on the eyes and the hardware!

 

[Granny]

When I first moved into my new house and started with the pool the TA wouldn't test at all -- there was so much acid in the pool from the pucks that nothing would register no telling how low the pH really was since 6.8 was as low as the test would read. I had to add about 16 lbs of baking soda before I could get a reading, I can't remember how much borax I used. Try testing the tap water for pH and alkalinity -- see what you get there. That should tell you if your test kit is good or not.

 

[BSpade]

More fun - so the idea of testing the tap water seems like a good one. For redundancy, I took a bottle of tap water to ACE and then I tested it, using the new HTH 6-way kit, and an old Aqua Chem kit and test strips that have been around for a while.

The results:
Ace: FC 0.1, TC 0.1, CC 0.0, pH 7.4, Hardness 30 ppm, Alk 44 ppm, Cya 0.2, Copper 0.3, Iron 0.1
(Alk is with 'stabilizer correction', whatever that means) - Never mind, the answer is here: http://www.troublefreepool.com/threads/49965-Stabilizer-Correction-for-Alkalinity-Tests

HTH 6-way: FC, TC, CC all 0.0, pH 7.4, Hardness 50, Alk 60, (Don't have enough reagent to 'play around' with CYA, no metals tests)

Aqua Chem: FC, TC, CC all 0.0, pH 7.4, Hardness 0, Alk 60

Test Strip: FC, TC, CC all 0.0, pH 7.2, Hardness 100, Alk 40 (I found the test strips in the Pool Cabinet, with an expiration date of 2008)

I assume that 'Hardness' is related to the difficulty of getting agreement out of multiple tests...


Also, just for fun, I took another sample to ACE, this one 1/2 Pool water, 1/2 tap water. I also did the same tests as above

Ace: FC 1.6, TC 2.0, CC 0.4, pH 6.5, Hardness 42, Alk 9ppm, CYA 107, Cu over 3.4 ppm, Fe 0

HTH 6-way: TC 3, pH 6.8, Hardness 100, ALK 50, (rest not tested)

Aqua Chem: TC 2, pH 6.8, Hardness 60, Alk 10, (rest not tested)


This is fun! Reminds me of my days in college as a Chemistry major (before the 6 1/2 hour Organic Chemistry lab turned me off Chemistry completely!)