PS234 1st Test Results

[DM]

Hello, Just received my kit, Thank You!
I've been having issues with my plaster being rough with calcium.
I have an IG, 40 x 18 free form, 3' to 6' deep, clorine, 3 years old.
I've been using Muratic Acid to keep the PH on the low side.
Here are the results:

FC 7
CC .5
TC 5
pH 7.3
Alk 70
Cal 540
Cya 100

I'd really appreciate your feedback.
Thank you
Denise

[prh129]

The first thing I noticed is your CYA is very high. According to Ben's best guess chart, your minimum FC should be 8. You might want to consider trying to lower the CYA by doing a partial drain and refill. Don't use any chlorine with CYA in it (di-chlor, tri-chlor pucks etc.) but try to stick with bleach.

I'm not an IG person but I believe your calcium level is very high also. In the thread below, it looks like the recommended Ca level for a plaster pool is between 200 and 400. The partial drain and refill should lower this also.

The alkalinity could be increased a bit with baking soda to between 80 and 125 but this can wait if you're going to do the drain and refill.

http://www.poolforum.com/pf2/showthread.php?t=2579

Peter

[DM]

A partial drain, that sounds drastic. I have a well that I just can't use for that and right now in my area the water companies, due to drought, won't fill a pool. There must be some other way to correct my water. And anyway I did that over the winter. We drained much lower than we should have and it filled all winter with the snow and rain. The chemistry was a mess at the end of the season.
How often should I do the water test?
Where do I find the charts to understand the numbers I get after testing?
Thank you
Denise

[let_her_flicker]

I copied this from the Alkalinity and Calcium Thread (2nd Sticky):

Why does CA matter?
CA is the portion of the TA that is due to "carbonates" from sodium bicarbonate (baking soda), sodium carbonate (soda ash), and other sources. On pools with concrete or limestone surfaces, low CA together with low pH will let your pool water DISSOLVE your pool surfaces, which is usually NOT a good thing. If your CA is high, your pool will tend to cloud up, any time you add calcium hypochlorite or raise the pH.


If your pool is not cloudy, I would not worry. I don't know anything about calcium building up on the plaster, but if it is something you can live with, maybe you can do a partial drain when season is over and let it refill with rain water.

With your CYA at that level you have, you will need to run you pool with higher chlorine levels to get proper chlorination.

Chlorine level should be 8ppm to 15 ppm. Shock to 25 ppm

Now one thing with higher CYA is that the chlorine added tends to be used up at a slower rate. You may have to chlorinate maybe once or twice a week. You will have to check and see how it goes.

Good Luck!

[duraleigh]

Flicker,

Now one thing with higher CYA is that the chlorine added tends to be used up at a slower rate. You may have to chlorinate maybe once or twice a week. You will have to check and see how it goes.

Well, not really. Most folks on this forum have to add chlorine more frequently than once per week. The consumption of chlorine is dictated by organics introduced into the pool.

Secondly, the Sun will destroy chlorine if it is not protected with CYA so, in some repects, that would mean the Cl does get consumed at a slower rate but it seems a little misleading to think you may only have to replenish weekly or bi-weekly.

[prh129]

How often should I do the water test?
Where do I find the charts to understand the numbers I get after testing?

Hi Denise,

How often you do the test is up to you. The OTO test is quick and easy so I would suggest you do that every day or every other day depending on how it fits into your schedule. Because you will have to run with higher chlorine (due to the high CYA) the OTO kit has a maximum reading of 5 ppm so you will have to do the dilution method to make it work - mix one part pool water with one part distilled water, test, and multiply the result by 2. (If that isn't enough you can do two parts distilled water and one part pool water and divide the result by 3.) You can do the other tests once a week or after a lot of people have been in the pool to check for CC. The alk and calcium shouldn't change that much so you might only do those once a month. If you are using pucks or other chlorine with CYA, then I would check the CYA every couple of weeks.

Other than the partial drain and refill, there is no good solution for lowering the CYA. There is a chemical out there that is supposed to lower CYA but I think the cost vs. performance was pretty poor. Over the winter it may get consumed by stuff that develops in the pool but if you can't do anything about it now, it shouldn't be a problem as long as you keep your chlorine where it needs to be.

This thread from the testing section has some guidelines for the things you are testing for and Ben;s best guess chart should give you the chlorine numbers you need.

http://www.poolforum.com/pf2/showthread.php?t=1113

Peter

[let_her_flicker]

Flicker,



Well, not really. Most folks on this forum have to add chlorine more frequently than once per week. The consumption of chlorine is dictated by organics introduced into the pool.

Secondly, the Sun will destroy chlorine if it is not protected with CYA so, in some repects, that would mean the Cl does get consumed at a slower rate but it seems a little misleading to think you may only have to replenish weekly or bi-weekly.

Dave,

Most people on this forum run their pools (including myself) in the 30 -50 range for CYA.

Running a pool at a higher CYA level (>100) was discussed at length on the old forum. A couple of people shared their results. Ben also discussed this at length.

To do it you had to have Ben's kit and test almost daily to see how fast the chlorine was being used up. This would only work after all the organics or anything else that would consume chlorine at a higher than normal rate were killed off. Normal organics (fecal material, bugs, leaves) consuming your chlorine are taken into account.

People shared their results that if you took it up to the high range of the best guess chart, 15 ppm it takes longer to lose 8 ppm of chlorine than it does if you run your in the 30 to 40 CYA range and chlorinate to 6 and have to add chlorine at 3 ppm (a loss of 3 ppm vs a loss of 7ppm.

I chlorinate every other day usually (96 oz of bleach) for use and direct sunlight with 35 ppm of CYA.

Now if you have triple the CYA that would theoretically you'd lose chlorine 3 times more slowly to direct sunlight. Yes, you would have to adjust for normal organics and you'd have to know your pool water. That is why Ben's kit with the FAS-DPD test would be essential to do this. I am not an expert of this subject, but a pool can be run successfully doing this.

Harry

[let_her_flicker]

Denise,

Your numbers look good except Total Chlorine is Free Chlorine + Combine Chlorine. In your case it would be 7 + .5 = 7.5 With your FC at that level, you are at the low end of the best guess chart for your pool's CYA level. You need to get the FC back up. Since you have Combined Chlorine (CC), I would raise my chlorine to the shock level of 25 ppm.

Secondly, since you have a high CA result, read up on Calcium in the Alkalinity and Calcium Thread.

http://www.poolforum.com/pf2/showthread.php?t=195

i would post there about the high calcium and if you need to do anything at all.

Good Luck and if you don't drain, maybe you could keep us posted on the loss of chlorine with CYA around 100 and how many times a week you have to chloriate to keep it within the operating range.

Harry