Time to replace sand?

[jonno]

Here are tonight's numbers:
FC 0.0
CC 3.5
pH 7.0
TA 210

Added 1 pint acid, brushed walls and bottom for 20 minutes or so, then added 6 gallons of bleach. I can just make out the brushhead when it is on the bottom in the shallow end so the visibility is slowly improving. At first I wondered why the TA increased from 190 to 210, but then realized I had a slow trickle of water running in over the past three days to bring up the level about 3" as the skimmer had started to suck air after backwashing this weekend. I tested our household water and the TA = 160, pH = 7.1. Our source is a spring/cistern that runs through a calcium carbonate & magnesium oxide acid neutralizer.

Thanks Janet - I'll stand by for Ben's response. Stocked up on bleach today...

[jonno]

Morning report:
FC 0.0
CC 4.5
pH 7.2
TA 200
There's a small amount of airy foam on the surface for the past couple of days - I imagine this is from the return riffling the surface, but I mention it here in case there is a larger significance. Since the pH has risen, I'll get some more acid today to keep it at or below 7.0.

[Watermom]

The foaming could be from the algaecide you added. That is a common side effect. (Also one of the reasons that the only algaecide we recommend is Polyquat 60%.)

[aylad]

Ben's response was to stick with the 6 gallon bleach doseage that he initially recommended. With large amounts of ammonia to break down, you're going to have higher than normal combined chlorine to deal with, that can be very irritating and uncomfortable. So..his recommendation was to break it down slowly with the lower doses of bleach, until you start getting CC readings of 1 or 2--at which time you can up the doseage and go ahead and get rid of it. So...stick with the 6 gallon dose for now.

I agree with Watermom on the foaming--it's likely evidence of the algaecide breaking down. Stay the course the way Ben recommended--and we'll help you get it cleaned up!!

Janet

[jonno]

Roger that and thanks! I'll stay the course and keep posting my numbers.

[jonno]

Evening report:
FC 2.3
CC 0.4 (tested twice to confirm both FC and CC)
pH 7.2 / 7.4
TA 190
After pulling the water sample, I added 1 pint acid, brushed the walls and bottom. Visibility unchanged over past two days (about 2'), then added 6 gallons of bleach. Still have scattering of light foam on the surface.

Since the CC was 0.4, I should up the bleach according to your post earlier today. How much?

Do you have any guess at the timeframe until this treatment clears the water up - days weeks?

I have questions about maintaining the pool with CYA so high (somewhere way over 100), but I'll wait until I get to that point before asking. Thanks!

[jonno]

Disregard yesterday evening's water tests! I messed up. Here are the morning numbers:
FC 0.5
CC 3.5
pH 7.2 / 7.4
TA 180
Since the pH is still up, even after last nitght's pint, I'll add another pint of acid this morning. No change in visibility. Still have scattering of light foam on the surface. Water is starting to look more green than blue - could it be another algae bloom?

[CarlD]

Remember to approach adding chemicals conservatively. Usually, bleach/chlorine is the exception but given your unusual circumstance even that should be done with care. Your FC is down so you need to raise it to the level Ben recommends.

Carl