pH stuck at 7.2

Jump to latest Follow Reply
GreatCanadian

GreatCanadian

0
LifeTime Supporter
Jul 28, 2011
842
St. John's, Newfoundland
Hello all,

Test results Friday,
CYA 50 (may be a touch more - tested after 5 days)
TA 70
FC 5
CC 0
CH 30
ph 7.2

I wanted to up the pH as it's been staying at 7.2, with children in the pool very often, and one of my returns pointed to the surface.

I added 28 oz of borax to raise the pH to 7.5. Tested Saturday morning. pH=7.2

This isn't the first time I've tried to raise my pH. But my pool seems to like it at 7.2. Water is perfectly clear, and the girls don't even bother to wear their goggles in the pool. They open their eyes underwater and says it doesn't sting at all. Very comfortable. No redness whatsoever. So, should I say to heck with it and let it stay at 7.2, or is it a little on the low side and should I do my best to raise it a bit. Also, the fill water from the tap reads a pH of at least 8.2.

GC
 
Your readings seem fine 70 TA might cause some slight pH bounce, I would add enough baking soda to get the TA at 80-100, which will also increase your pH as you do slightly.

7.2pH is at the bottom of the reccommended level for water chemistry but certainly not outwith the recommended levels, so you may well be better with the timely saying "if it aint broke, dont fix it"
 
In a liner pool a Langelier Saturation Index of -1.2 is not really a concern according to this websites authorities, in GB we would still reccommend increasing CH and pH to reach a more neutral level as we believe a low SI to still be erosive/corrosive to plant equipment ie your boiler and pump, it is certainly safe to swim in, and would pass most authority codes in the US or Europe.

Regards
Stuart
 
The way we are trained over here is that irrelevant of wether your pool is liner etc maintaining a good saturation index will prevent problems down the road, negative SI values are still corrosive so they are going to try and eat something - where is there calcium or metals available in a swimming pool which is all plastic for your water to devour? Your pump, your heat exchanger and your SWG unit. Admittedly pool water will take longer to start erroding and corroding metal than it will plaster but it will attack it given the chance, if you are in a soft water area the simplest proof is in the kettle, just look at the element at the bottom, its being eaten all the time by the acid water that we use to boil in it, whereas in the south of England they need scale inhibitor to stop the build up of calcium deposits.

I don't want to scaremonger as that will take a lot longer to happen in a pool as the rest of the factors are correct, I would reccommend you increase CH by using Calcium Hypochorite for a while, it really doesn't increase CH as dramatically as is suggested sometimes on this site though, so would take some considerable time to reach the magical 200 figure for correct CH levels, even with CAl Hypo I still had to boost a new pool I was running by using Calcium Chloride by adding around 6kg (25,000 imp Gallon)

Going back to your pH problem UK methology is a starting point for pH buffering with TA levels is 80, again irrelevant of pool construction, we site that pH will still fluctuate below 80, and that 100 is a good number to be at.

I think your options to increase pH are move to 90 on TA, using borax, I have no experience of the borates system so am only going by the teaching of others on here, but if it does assist in stabilising pH alongside TA, then this may well be good for you, and it will increase your TA at the same time.

Stuart
 
CH may be a factor for your heater, but I am fairly positive soft water is of no issue for pump and SWG.

You may want to check the heater mfr's recommendations first, however baring that, soft water is a good thing IMO. It sure as heck feels better after a shower (we're so very spoiled... we actually complain about showers and how water tastes/feels elsewhere. I couldn't even brush my teeth without feeling like hurling using the tap water at one friend's house in CA).

I keep my TA around 70, with borates at 50ppm and pH seems to settle and stick at around 7.4. Now that we've added the SWG I've been expecting it to rise but it hasn't. TFP recommends TA at 60-80ppm for a SWG pool. I don't see any reason to raise TA to 90ppm, or mess with it at all at this point. Borates may help stabilize pH, and I think you'll enjoy the way it makes the water look and feel should you chose to try it.

I use the kids to judge if pH is ok. If they say they can open their eyes comfortably underwater, no stinging... I'm happy wherever it's at between 7.2 and 7.8.
 
You are fine where your at. It sounds like your pool wants to be at 7.2 and as long as it goes no lower, you are good. Look at it this way, 99.9% of the other members here wish they had your situation. :)
 

Enjoying this content?

Support TFP with a donation.

Give Support
Yeah, it sure seems like that's where it wants to be. I had 4 kids in the pool for over 6 hours on Sunday and at least 4 hours on Saturday, all going crazy. I have one of my returns turned straight up, and the water is boiling in that spot, and pH still 7.2. And if I do nothing - no kids in the pool, and no aeration, pH stays at 7.2. I guess I won't worry about it, and just keep an eye on it in case it decides to take a dip. Thanks for your replies.

Frogabog - my heater manual only says "No chemical exclusions".
I intend to try the borates. No rush though. My pool seems perfect, so I'm ok with it as is. But I do want to give the borates a shot just to see what it's like. Like you, I'm ok when the kids find the water easy on the eyes. I would just feel more comfortable if the pH were a little higher. At 7.2 I have no cushion if it decides to dip, so I'm always wondering about it, and testing it sometimes twice a day.

GC
 
Most pools will rise in pH naturally. Pretty much the only things that I've found that cause pH to dip is trichlor and rain. Rain, just a tad, but trichlor can dump it rapidly.

You could raise the pH chemically, a little borax just to get it up t 7.3 or 7.4 if that makes you feel better. At the levels you're at now, doing borax would be easy (TA 70, pH 7.2) and should fall right in line. Add borax, pH spikes... add acid... back down to 7.2. Add the rest of the borax, then acid... and you should be set. As far as the bugs, I do think it helps and we love the feel and sparkle. At night you can really tell, the water/light reflecting off the trees above dances more.

You could also do it in measured stages so that pH only rises to 8 each time instead of an unknown value above 8. It could take three stages this way. I've always broadcasted the borax, then brush to mix. Seems to work just fine.
 
According to Pool Calculator, 28 ounces of Borax would raise my pH from 7.2 to 7.5. I added 28 ounces on Friday, and at Saturday morning my pH was still 7.2. Next time I will measure an hour after adding the borax. Perhaps it did rise to 7.5, but the pool gods sucked it back down to 7.2 because that's where my pool is happy!!!
 
What was your TA at the time? You could try raising TA by 10ppm. See if it sticks better at 80ppm.

The borates at 50ppm will make pH more difficult to move, both with aeration and chemically. But, once it sticks you shouldn't have to move it much or very often.
 
Keep in mind that the accuracy of the TA test is roughly plus or minus 10ppm. Generally, you can get a little closer than that but adjusting TA by increments of exactly 10 involves some luck.
 
Whispers quietly- (I can't answer that yet, as I haven't ordered the full test kit,......) I have switched to liquid chlorine and have tried adding the Borax, only to have it drop back to 7.2. Since it's clear and I know I don't have excess CYA, I am just riding out the rest of our short central PA swim season and odering the test kit and upgrades over the winter.
 

Enjoying this content?

Support TFP with a donation.

Give Support
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply