ready to bulldoze pool

[desperate]

I have had this pool for 21 years. The last couple of years has been a nightmare. I drained the pool completely last year and brushed down the plaster with a wire brush, cleaned it up and refilled it. About 12 months later, I still can't keep it right.

Stats:
free available 1
total available 2
PH 7.2
total alkalinity 220
CYA 40
Tot Dissolved solids 2500

water is cloudy
Last Thursday night I superchlorinated, left town Friday and returned Monday.
Pump ran on low 24 hours a day. Chlorinator used (6) 3" tablets...plus I had two floaters with 3 pills each in the pool.
When I returned Monday, chlorine was .5

I have spent a fortune the last two months on chemicals. Yesterday I had my water tested at 5 pool stores some of the measures were very different.

Consensus is that I need to drain at least 1/3 of my water and put a sealer on the flagstone that touches the pool. One pool person wondered if something is leaching through the plaster (replaster the pool).

If anyone has suggestions, I would appreciate it.
thanx

[muss08]

TA is way too high. Is this the same person who has been conferring with chemgeek? If so, you know how to get your TA down. The fact that you are losing so much chlorine tells me your water is still killing organic materials in the pool. Plus with a FC of 1 and a TC of 2 this means you have a combined chlorine of 1. FC+CC=TC. Combined chlorine is a byproduct of chlorine oxidizing organic materials. Keeping your chlorine at the proper level will stop the combined chlorine. With a CYA of 40 your FC needs to be 4ppm. Continue to shock daily until your free chlorine level holds overnight. This will ensure everything is dead. Continue to brush daily and backwash. You need a good test kit- not strips. Taylor K 2006 is the best i've used and can usually be found for about $50-$60. You could switch to using bleach instead of the pucks and even shock. Regular clorox works and should save you a bit of money.

[desperate]

thanks, and interesting. I did have one store tell me to shock with 8 gallons of liquid chlorine. Does this fall in line with what you are suggesting? I also had two others tell me that since my TDL was 2500 to 3000, nothing I do will help....only drain the pool. They said liquid chlorine would just raise the TDL even more and make matters worse.

[desperate]

Oh, and no I have not been conferring with anybody on-line. I just registered on this site.

[muss08]

Okay, I thought I saw someone on here with a similar name and similar test results. I apologize because I did not see your TDS readings. 2500 is way too high or if I did I thought it read 250. Chlorine will be VERY ineffective at that level. Normal TDS is 250-1500ppm. It doesnt make sense to me that your TDS would be that high if you just drained it last year. You said you went to more than one store and they all said your TDS was high? Unfortunately the only way to get the TDS down is to drain your pool- i would suggest 3/4- that'll get it down to about 600. 1/3 would only get it down to about 1700 which is still too high. How do you fill your pool? Garden hose? Are you on a well? I would get your fill water tested as well. That may be the problem if the fill water has a high TDS.

[chem geek]

Some things don't make sense. I'm not sure I trust the measured numbers. The pool was completely drained and refilled last year, so how did the TDS get to 2500? TDS is usually mostly salt and is not a problem for chlorine. The reason this became industry lore is that higher TDS was usually associated with older pools where the CYA had built up as well and the blame for problems was on the TDS when it was really the high CYA (without correspondingly higher FC) that was to blame. What is important is not TDS itself, but what the TDS is composed of -- bicarbonate (TA), cyanuric acid (CYA), calcium hardness (CH), salt (sodium chloride). Water that is older can build up organics some of which may not fully dissolve [EDIT] or get oxidized [END-EDIT] so that can be cloudy, but normal chlorine and filtration take care of them in most cases.

There was no measurement of Calcium Hardness. The Total Alkalinity (TA) is already high so if the CH is high then if the pH rises one could get cloudiness or scaling. As muss08 mentioned, please, please, please get yourself a Taylor K-2006 test kit for a good online price here or the TF100 kit from tftestkits(dot)com here with the latter kit having 36% more volume of reagents so comparably priced "per test".

When you say you superchlorinated, what kind of chlorine did you use (brand and product name)? The fact that you aren't holding chlorine and the water is cloudy does point to a pending algae bloom. If the CYA measurement were accurate at 40 ppm, then shocking to a Free Chlorine (FC) level of 16 ppm would be appropriate and then keep adding chlorine to hold that FC and filter 24/7 until three things occur: 1) the water becomes clear, 2) there is minimal drop in FC overnight (< 1 ppm), 3) there is minimal measured Combined Chlorine (CC) <= 0.5 ppm.

However, again, get yourself a good test kit since I don't trust those numbers. In the meantime, just use a 16 ppm FC target and use chlorinating liquid or unscented 6% bleach (e.g. Clorox Regular or off-brand Ultra).

Richard

[muss08]

Always teaching me something new chemgeek. Didnt know about the TDS lore. Dont you love the APSP?

[desperate]

I tried to reply several times today and kept getting errors. This is a test. then I will send more info

[desperate]

Thank you muss08 and chem geek,

ok, tuesday the 13th I went to 5 pool stores, three of them were Leslie's one was warehouse pools and the fifth was a local. The last two had computerized testing equipment.

Free chl 3 .5 1 .6 1
Tot chl 3 2 2 1.2 1
PH 7.0 7.1 7.2 7.3 7.0
TA 210 250 220 180 225
Hardness 675
CYA 60 200 35 120 150
TDS 3000 2500 2500 2100 2500
phosphate 100

One of the testers expressed a concern that maybe something was leaching through my plaster and that i may need to replaster. She also said that I should not have so many chlorinators. Another thing that has been going on the last couple of years is that the flagstone coping that i have is slick and chalky to the touch where it is touching water Also the bottom ball valve on my lifegard chlorinator only lasts about three weeks and then gets stuck.

Nobody ever uses this pool. I work on it, go to the lake for the weekend and then start all over when I get back.

Thanks to both of you
will

[desperate]

Oh, chem geek, i forgot.

I have gone thru so many chemicals.....I think I super-chlorinated last week with Pool Brand from SAMS. It is a Sodium Dichloro

[chem geek]

Please do not ever, ever shock the pool with a chemical that says "...dichloro..." in it. It just adds to the CYA level making the chlorine less effective.

You can see the huge variation in the CYA numbers from the pool stores. Also, no one measured Calcium Hardness and one measured "Hardness" which I'm guessing is "Total Hardness" (is that right or did they tell you this was explicitly Calcium Hardness?). Please get your own test kit so that you can get accurate measurements yourself. You can get a Taylor K-2006 test kit here or a TF100 test kit from tftestkits(dot)com here with the latter having 36% more volume of reagents so comparably priced "per test".

If the "Hardness" number were really Calcium Hardness, then your numbers result in a saturation index of +0.2 to +0.3 which isn't horribly over-saturated, but if the pH were to go up the water could get cloudy and eventually you could get scale. Your TA is high and for whatever strange reason your TDS is higher than expected, though with the TA and CH numbers one would have a typical minimum TDS of around 1100 anyway so the balance might be magnesium if the Hardness number were truly Calcium Hardness.

I suspect that since most of the CYA numbers were high and since you've used Trichlor pucks/tabs, that the cloudiness could be nascent algae (you'd usually see a drop in FC level overnight if that were the case). However, the high TA and CH could mean that the cloudiness is some over-saturation of calcium carbonate. This is why you really, really need to get your own test kit and get accurate numbers. If the CYA is high, then a partial drain/refill will be needed. If it's not, then we'll lower the TA as muss08 first suggested. When you get your test kit, you'll want to test your fill water as well as your pool water.

In the meantime, if you just wanted to start on a partial drain/refill, that wouldn't be bad in any event. It should lower the TA and CH levels unless those are high in your fill water and will certainly lower the CYA level.

By the way, I discovered that you cannot use the word "bet ting" (remove the space) without getting a "spam" warning and inability to post a message. How annoying!

Richard

[desperate]

I think the Hardness measurement is Calcium Hardness.

I really appreciate ya'll's help. I think I am just going to drain the whole thing again. Water will cost me $50 for half drain 10,000 gal, or $100 for 20,000 gal.

This has been such a hassle since I have followed too much bad advice as well as guessing what to do. So, after refill, I need to come back to you guys and learn what to do as if I new nothing.

One concern I still have is my plaster and flagstone coping. It has been suggested that I seal my flagstone where it touches the water. (I currently get chalky residue when I touch it). One person said she was concerned that maybe something is leaching through my plaster causing the (TDS) and maybe I should re-plaster.

How do I determine if any of this is neccessary.
Thanks again

[muss08]

My best guess would be that the chalky residue on your flagstone is scale from the pool. I dont know if chemgeek has ever heard of something leaching through plaster or not but I have not. EXCEPT when someone has a very low calcium hardness the calcium in the plaster can leach out. Something would have to be leaching through 6-12" of gunite then the 1/2-1/4" of the plaster finish. How old is your plaster? Is it very rough? When empty have you ever lightly tapped all around with a hammer and heard any hollow sounds? Are there any areas around the pool where the plaster is gone and you can see the brown gunite underneath? These factors are what you should consider for replastering. The plaster finish is very thin so IF IF IF something is leaching through the plaster it would still do it with new plaster. Why is your coping touching the water? Could you post a pic so we can see?

[muss08]

Oh yeah- test the fill water!

[chem geek]

There is something called efflorescence which is described here. If the ground behind some of the plaster is watered a lot and the construction wasn't great, then water can leach through from the ground through concrete. I don't know if that is what is happening in this case.