High PH issues with Stenner and liquid chlorine.

[miwitte]

Been doing the liquid chlorine route with the Stenner and timer for 3 years now and pool has been great. This year every time it injects it seems to raise my PH and it gets to 8 so i need to add PH-Down to get it back down. Seems about every 2-4 days it gets too high. I have tried various Alkalinity levels, mine has always liked somewhere in the 70 range and I am now up to 120 ppm trying to sort this out.

The liner was replaced this year so not sure if that's part of it but really cant control PH right now. The guy that installed the liner said liquid chlorine increases PH but Ive been doing this 3 years and never had such swings. The only thing that's different is the liquid chlorine I have used for years (Pool Essentials) ,which I had always gotten at Lowes of Walmart and they carry same brand. There was a run on liquid chlorine and could'nt find it and Lowe's had a different brand called Kemtech and I bought like 60 of them so been using that. The only variable is the new liner and brand of chlorine.

I lowered PH (Again) last night and here is the levels this AM. They are perfect, i just cant control the PH rise. I have tried this at every TA from 60-120ppm in 10 ppm steps to no avail. Like i said previously I ran the TA at 70 the last couple of years and never had the PH bounce this bad.
I am using the Taylor test kit and reagents were new this year from Amazon.

With pool temp at 88 my CSI is + .06
FC-7 ppm
TC-0 ppm
CYA-50-60 ppm(hard to tell sometimes in the tube)
PH-7.6 ppm
TA-120 ppm
CH-220 ppm

 

[mknauss]

Like i said previously I ran the TA at 70 the last couple of years and never had the PH bounce this bad.

There is your answer. High TA like you have will make your pH rise much quicker.

 

[Chasarms]

My TA was at 140 early in the season. I'm not sure why. I had the same issues. I would put enough MA in the water to lower pH to 7.6, and it would be back to 8 in just a couple of days. The MA seemed to have negligible effect on the TA. So, I started dosing bigger. When pH crossed over 7.8, I dosed in larger doses, using pool math to target a pH of 7.2 or so. The pH still would rise back to 7.8 within a week or so, but after a couple of the larger doses, I did start to see TA start to improve.

I am in the 90-100 range now, and I plan to keep this approach up until I get TA down to TFP targets. The thing is, now that the TA has come down some, the pH rise is a little slower, so I can't dose as often. I went eight days before needing it this last time.

 

[duraleigh]

I Agree with mknauss........lower your TA via the method found in pool school and your rate of climb almost surely will slow down a lot.

Use muriatic acid during the TA lowering process. Please don't use "pH down".

The article on the correct way to lower TA is in Pool School.

 

[miwitte]

so the odd thing is that i have been having this issue since day one of the new pool. at that point TA was 60-70 and i kept it there for at least a month. Then decided to go up by 10ppm every week to see if it made difference.

 

[Flying Tivo]

Then decided to go up by 10ppm every week to see if it made difference.

You can go as low as 50 but no more, acid additions is a fact of life in pool ownership.

 

[duraleigh]

decided to go up by 10ppm every week to see if it made difference.

We are saying you went the wrong way. Drop your TA down to 60 and you will still add acid but you will do it less frequently.

 

[miwitte]

gothca. So i need to get some kind of fountain that sprays water up to help reduce TA, and reduce PH which will reduce TA as well.

Quesition on why not use "PH Down" from Clorox VS muriatic acid. Seems safer plus i have a bunch of it.

 

[duraleigh]

pH down is sodium bisulphate and leaves a residual of sulfates in the pool over time. Muriatic is likely cheaper and leaves NOTHING in your pool.

I also just read something that I wasn't aware of.......pH down asks for a wait time of 6 hours.......does it say that on your container?

So, if you have it on hand I think I would use it but I wouldn't continually use it. Muriatic requires common sense but it is handles by thousands and thousands of pool folks every day.

 

[miwitte]

ok ill get some and report back in a week or so how things look.

 

[miwitte]

So i got aerator fountains(with lights they are cool at night, and have gotten TA down to 70, PH looks more stable over the last 3-4 days. if i still see bounce ill go to 60 but looks better.

Now another curve ball. I am going on vacation in a couple weeks, and my pool uses about a gallon of 10% a day. I have a 5 gallon pail attached to stenner so typically its enough for 4 days. I used to have 2 buckets with a 1/4" tee, but it would melt the plastic and i tried brass 1/4' ones from lowes and they would gum up with green goop I assume from the reaction to the chlorine. Plus i think it was putting metals as i had some weird staining. I have not been able to find a 1/4" Tee that is chemical resistant i looked in grangers and other places.

I am thinking of either a) reducing the timer to inject maybe 1/2 gallon and use pucks, or b) turn off liquid chlorine and just use the pucks. Ill have to start testing usage this week as its a brand new pump, filter, off line chlorinator so will take a little while to find the right settings. Right now my CYA is 50 so should be pretty safe to use just pucks for 2 weeks without raising CYA too much.

Im still learning the pool systems as i had a neighbors 90' pine tree tree drop in the pool in Jan took out the liner, pump, heater etc so all brand new gear from insurance. I have the Stenner timer dialed in but havent played with off line clorinator yet. I think b) would be the safer choice.