pH constantly rising

[bparker]

I switched to salt this year, and pool remodel/replaster (done in March '17) reduced size to 20K gal. I am still trying to get things settled down and pH is my current problem. I am adding 16-32 oz. muriatic daily to keep it at 7.8. Posting here since it seems SWCG raises pH.

TA has been rock solid at 70 ppm. FC is finally settling down at 4.5 with IC40 set to 23% and pump running 22 hrs. at 1050 rpm, then 2 hrs at 2000 for the Polaris. CH tends to creep higher although I have never added anything. 225 up to 450. My Taylor kit currently says 425 (had a lot of rain). As a check, Leslies test says 325. My reagents may be a year or 2 old. Pool fill water measures at CH 100. My CYA test says 50-60. Leslies test says 70. Just finished adding 4 lbs. stabilizer over the last couple weeks.

Looking at recommended levels, I seem to be in ballpark. But I question the difference in my readings vs. Leslies for CH and CYA. Having to reduce pH every day is a pita.

Oh, I rarely run the bubbler/deck jets, so aeration is not likely an issue.

 

[jblizzle]

Running the SWG will drive the pH up some. If the TA could get lowered a bit, it may slow the pH rise.

If you raise the CYA up to 80ppm, then you would not need to run the SWG as much and then it would not drive the pH up as much.

CH is going to continue to rise in the water due to evaporation and then adding top-off water ... harvesting rain water can help to keep it lower.

Do yourself a favor and stop having your water tested at the pool store. Trust your test kit (which one do you have)? If the reagents are over a year or at 2 years old, consider ordering replacements. FYI, tftestkits.net has a sale on refills every March.

 

[JVTrain]

Bubblers, deck jets and SWG. Lots of aeration will drive that pH upward. Your TA is fairly low but could even allow it to get a little lower. Don't let it go below 50 though. You could consider borates to help with pH rise. I don't have direct experience with it myself, but there is some evidence here on the forums that it can help stabilize pH rise. Check out this thread that discusses borates Borates - Why and How

 

[Ocgasman]

in addition to the SWG, your plaster is still curing from your 03/17 remodel. You might be battling rising pH for awhile but it will probably slow down eventually when your pool finds it's equilibrium. As stated above, lowering TA will help and so will adding Borates. My pool has a huge hunger for acid as I have tons of aeration from a negative edge. I got tired of adding acid everyday. So I installed an IntellipH. For my pool, best investment ever. Once I have the IntellipH dialed in, it's smooth sailing with my pH.

 

[ctrav]

Is the IntellipH in addition to the SWG or does it replace? Thanks...

in addition to the SWG, your plaster is still curing from your 03/17 remodel. You might be battling rising pH for awhile but it will probably slow down eventually when your pool finds it's equilibrium. As stated above, lowering TA will help and so will adding Borates. My pool has a huge hunger for acid as I have tons of aeration from a negative edge. I got tired of adding acid everyday. So I installed an IntellipH. For my pool, best investment ever. Once I have the IntellipH dialed in, it's smooth sailing with my pH.

 

[jblizzle]

In addition to the SWG ... it just adds MA to lower pH.

 

[bparker]

I guess my next test will be to reduce pump time and increase Cl output from the cell to see how much impact there is on pH. I liked running the pump all day (at only 120 watts). Water is crystal clear even with sand filter.

 

[pooldv]

Running the pump is ok as long as the bubbles/waterfall aren't on. My pump runs 8a to 10p or 10p to 8a or 24x7 depending on whether I am heating, cooling or the trees are busy.

 

[bparker]

I had not thought of running the pump at night vs. day to get the little extra cooling.

 

[pooldv]

Aha, it's the little things. Yes, I've found that it can make a 1-2 degree difference running day only when heating or night only when cooling.