Acid Bath to normalize replaster coloring + Soda Ash = cloudy water & precipitate

[boltonguy]

I completed a re-plaster with WetEdge Luna Quartz about a month ago. After 2 weeks of brushing 2x per day and keeping pH & chlorine balanced the water was clear but I noticed footprints, etc. in the coloration of the plaster.

PB came back and did a suspended acid bath for 7 days, pouring 15 gal of MA into my 18k gal inground pool. I brushed again daily (some times 2x per day) but didn't balance the water as the pump was off. Yesterday evening they came back to balance the water and put (I think) 24 lbs of soda ash (at least that is what the receipt says) into the pool, brushed and turned on the pump. I have been running the pump since they balanced the water. At that time, I noticed that chlorine was almost at zero so I poured in a gallon of liquid shock.

This morning I have milky water (esp in deep end where the precipitate has settled) and settled precipitate in many areas. The DE filter was full so I backwashed, threw on my suction-side cleaner to pick up the precipitate and tested the water after backwashing again:

pH: 6.8
FC: 3+
TC: 3+
TA: 150
CH: 800
CYA: 50

I think from reading other threads that the precipitate is coming from my CH being so high and interacting with the soda ash, and the pH staying low because the TA is so high.

Any thoughts? I left the PB a vmail this morning but haven't yet heard back. it is in the 80s and my wife is asking if the kids can swim today or tomorrow as the tech last night said we should be able to swim today. I cant see the drain covers owing to the volume of precipitate in the deep end, so my answer is "no."

Thx,
David

 

[JoyfulNoise]

Re: Acid Bath to normalize replaster coloring + Soda Ash = cloudy water & precipitate

Please add your pool details to your signature, it helps us to debug problems better and cuts down on a lot of the unnecessary back & forth clarification questions.

With TA and CH that high, soda ash would definitely cause calcium carbonate to precipitate out. You'll need to run your filter for it to clear. Depending on what filter type you have, it could take a while.

TA does not hold down your pH; quite the the opposite. High TA typically leads to pH rise through aeration and outgassing of CO2 from the water. You can try to aerate your water with any kind of water feature you might have (spa spillover, waterfalls, etc). Even brushing vigorously helps aerate the water. If you want to raise your pH faster, use 20 Mule Team borax to raise pH as it will not add any extra alkalinity to your water. Eventually, once you get your water balanced again, you're going to need to bring that TA down.