Help At Wits End!

Problems relating to pH and total alkalinity.
Increase ph, increase TA. Reduce pH, reduce TA.
pH chemistry advice and techniques for the pool.
versley
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My Pool: 12000 gal in ground, sand filter
Location: San Antonio

Help At Wits End!

Postby versley » Mon 27 Jun, 2011 13:34

I am at wits end with our pool and every time I go to the pool store their recommendations make it worse. It is so bad now they have no answers. I will try to describe all the problems the best I can.

It started off with the PH and Alk being slightly low, ph 6.8. I was told to add 6 lbs of soda ash, which I did with no trouble bringing it up slightly, then added another 4 lbs. All was fine except ph was only at 7.0 and we had some algae. Pool store said add more soda ash. So one week after initial treatment I added 4 lbs and it turned cloudy and never cleared up and seemed to all settle on the bottom. We tried arriating for another week but still remained totally cloudy (can't see the bottom cloudy). So we vaccuumed to waste and it started clearing.

However the soda ash raised the alkalinity level to 180 with ph still bouncing around 6.7 - 6.9.

Again I waited another week and tried about 3 lbs of soda ash. This time totally dissolving it in a bucket and slowly adding it. Again very cloudy without clearing and ash settled to the bottom. re-vaccummed. It raised the alk more but not the ph.

Now the store has no answers as to why the soda ash is not dissolving into the water or raising ph. I am tired of vaccuming it out to waste! I know draining the pool would be the ultimate answer but in Texas with water restrictions this is not possible in the summer.......

I bought a good test kit and this morning tested my water. First thing, chlorine, as soon as I put the first drops into the tester to neutralize the water it turned cloudy as could be. Just like the soda did. This never happened before?

I included pool store readings from last week in ()
Anyway chlorine was high, but it has been bouncing from high to none....
Ph was 6.8 (7.0)
Alkinlinity was 150 (120) but has been as high as 180
Cyan acid, too high to read on my tester as it stops at 100 (125)
phosphate (300)

We also are having bouts with algae even with high cl readings.

Our pool is 12000 gal in ground and we are using 3" tablets (with auto dispenser)
I have used a copper algaecide for the algae in the past.

One pool guy told me the problem was I had used a lb of cal hypo shock 3 weeks ago and not to use so been using di-clor as a shock .

Not sure what else to tell you. I am not a chemist and do not where to turn. All has been fine for 9 years except for some algae problems and a continual battle with low ph all the time.

Please anyone that can help I would appreciate it so much!! I am ready to fill it with sand and forget it!


chem geek
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Help At Wits End!

Postby chem geek » Mon 27 Jun, 2011 21:49

Do NOT use Dichlor since your CYA is already too high. The following are chemical facts that are independent of concentration of product or of pool size:

For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.
For every 10 ppm FC added by Cal-Hypo, it also increases Calcium Hardness (CH) by at least 7 ppm.

You need to do a partial drain/refill to lower your CYA level. The higher CYA makes the chlorine less effective and it would take extraordinary levels to prevent algae growth in the pool and to oxidize fast enough. As for your pH and TA, with a higher TA all you need to do is aerate the water to raise the pH. The fact that your pH got so low probably means you were using Trichlor pucks/tabs and that is also probably how you got your CYA so high. Read the Pool School to learn more about how to properly maintain your pool.

You didn't report Calcium Hardness (CH) so I'm not sure what kind of test kit you have. The best are either the Taylor K-2006 or the TFTestkits TF-100 .
versley
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Posts: 4
Joined: Mon 27 Jun, 2011 11:48
My Pool: 12000 gal in ground, sand filter
Location: San Antonio

Help At Wits End!

Postby versley » Mon 27 Jun, 2011 22:11

Thanks for the reply.

I know draining is the answer but are limited here because of drought restrictions....

I understand what you told me but what I don't understand is what is preventing the soda ash from dissolving into the water and causing even my sample water to cloud in the tester when I add the neutralizer. No one here locally can tell me. It has to be a chemical reaction and nowhere in my reading can I find the answer.

We just got through this evening vacuuming to waste again and adding clean water. Yes we are using the 3" tablets and will go read "pool school" to see what our alternatives are. I assume liquid chlorine is the choice...

We have hard water here and will get the pool store to check it as I was getting like a 800 or so.
chem geek
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Help At Wits End!

Postby chem geek » Tue 28 Jun, 2011 01:31

The pH Up won't dissolve and causes the water to cloud up because your Calcium Hardness (CH) and now your Total Alkalinity (TA) are both high. If it weren't for the low pH, the water would be over-saturated with calcium carbonate and any addition of either calcium (as in calcium chloride) or carbonate (as with sodium carbonate) would cloud the water. pH Up (sodium carbonate) should NOT have been used to raise the pH since it raises the TA too much and the CH was very high. With a very high CH, you'd need to keep your TA and pH both low. If one has to increase the pH then if the TA is high one can aerate the water and if not then one can use 20 Mule Team Borax for raising the pH since it does not add carbonates.

Anyway, at this point if you aerate the water the pH should rise a bit and you can then add acid to lower the TA. The procedure is described in this post. After you find out the true CH, you may need to use an anti-scale calcium sequestrant product to prevent scaling and cloudiness.

I'm not sure why the chlorine neutralizer (I presume you mean in the TA test) clouds the water unless perhaps it causes the pH to rise (this is a known problem with thiosulfate solutions) which caused precipitation of calcium carbonate.

Yes, you are correct that you want to use chlorinating liquid or 6% bleach for chlorine. Trichlor or Dichlor will increase CYA while Cal-Hypo will increase CH.
LisaLovesHerPool
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My Pool: I have a 14' above ground rise & fill pool. This is my first year 2011 to have a pool.
Location: Indiana

Help At Wits End!

Postby LisaLovesHerPool » Tue 05 Jul, 2011 23:29

:roll: This is my first year at running a pool. I thought I would start out with a medium one to get the hang of it. I bought a 14' above ground 'rise and fill' pool. I filled it up, installed the filter without petroleum jelly as they recommended. I had a small leak from the filter but it was tolerable. So yesterday I decided to check what was plugging up the suction inside the pump. So I reached over & tried to take the lid off of the pump while it was running & the hoses were not plugged off. (I now realize this is not a good idea) So it spewed out water EVERYWHERE & I ran & shut the pump off. I have since FAILED at sealing anything on the pump! I have tried relighting the brackets, checking connections of the hoses, holding it up in the air to drain out the water so I can put the filter in and seal the top, but seconds into the filter filling with water it spews out of the top & where the hose connects to the filter pump.
The ONLY thing I can think of is to plug the inside of the pool and disable the whole thing & start over. With petroleum jelly as it said to in the first place.
Help? :wtf:
versley
Pool Newbie
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Posts: 4
Joined: Mon 27 Jun, 2011 11:48
My Pool: 12000 gal in ground, sand filter
Location: San Antonio

Help At Wits End!

Postby versley » Thu 21 Jul, 2011 14:29

Okay been a while since I last wrote and here are the current readings....
Chlorine 5
CH 670
CY Acid 150
Alk 90
PH 7.0
Iron .15

The Alk has gone down considerably and the PH has risen a bit. According to Leslies, I need to use Metal Free to get the metals out so the PH will rise. I have been aerating all this time and also tried adding some soda to a bit of pool water in a bucket to test if it would dissolve ( it did not).

I am going to first add a flockulent since we have a green dust in the pool and then vaccuum to waste. Then going to add the metal free and once those are removed going to add a calcium hardness reducer.

Does this sound like the correct way to treat the problem?

I will see where the ph is after all this.....

I looked into liquid chlorine but have not found a place to get it here in town, so may have to resort to reg chlorine from the grocery store until we can drain the pool in the fall.
czechmate
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My Pool: 16 x 32 gunite21000 gal., Diamond Brite Blue, Swimquip XL pump, DE36
Location: Texas

Help At Wits End!

Postby czechmate » Thu 21 Jul, 2011 15:46

Your pool is a top candidate for a complete water change. That is if your numbers are correct.
Go to Pool Calculator and you will see that your plaster is endagered, never mind that you can not fight of algae bloom start without 10 ppm of chlorine present at all times!
BTW, New plaster will cost you still more, than the chlorine!
versley
Pool Newbie
Pool Newbie
Posts: 4
Joined: Mon 27 Jun, 2011 11:48
My Pool: 12000 gal in ground, sand filter
Location: San Antonio

Help At Wits End!

Postby versley » Thu 21 Jul, 2011 16:22

Thanks but if you read the entire thread you will see I am in Texas in the middle of a drought and we have water restrictions that are being enforced to the max. Thus I cannot drain the pool at this time. That is why I am trying to baby it along until fall when we can drain it. It is against the law right now to drain and or refill any pools.......if not it would have already been drained!
czechmate
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Posts: 401
Joined: Sat 16 May, 2009 09:20
My Pool: 16 x 32 gunite21000 gal., Diamond Brite Blue, Swimquip XL pump, DE36
Location: Texas

Help At Wits End!

Postby czechmate » Fri 22 Jul, 2011 15:16

For the time being lower your PH to 7.5-7.6. It will hold you of plaster problems for now.

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