Correct Order?

[Pepperdinegal]

OKay, so we installed the SWG today in preparation and I just balanced all my chemicals. They are as follows:

pH - 7.8
FC - 3ppm
CYA - 60 (up from 25 this morning after adding 3 gallons of conditioner)
TA - 140 (I know this needs to come in, but not my focus right now)

We purchased 800lbs of Diamond Solar Salt today and my tester says I currently have 600ppm salt in my pool (not sure where it came from). My plan is to add the amount the calculator says to get to 3200 and then retest. I’m afraid to overshoot it. Here’s my plan…

Retest pH and chlorine in the morning. Hopefully pH will still be 7.8 and I’ll add whatever amount of chlorine the pool calculator says I need to get up to 6ppm. Then I’ll dump the salt in and brush a few times throughout the day. Then, once dissolved, I’ll fire up the generator at 50%. My pump runs at 2100rpms for 14 hours. I’ll watch and monitor my FC levels for the next week to make sure it’s keeping. Sound like an okay plan?? Anything else I need to do before adding the salt and starting the generator? Thanks!

 

[mknauss]

I currently have 600ppm salt in my pool (not sure where it came from).

Fill water, liquid chlorine, muriatic acid, sweat, etc all add salt to the pool water.

Add 2/3 rds of the salt needed the first time. So for you, that is about 500 lbs. Let that dissolve, mix in, pump running, for 24 hours. Then test the salinity again, and add what is needed to get to your goal. Run the pump, etc for 24 hours and then start the SWCG.

 

[mknauss]

What SWCG did you install? Please add to your signature.

What is the CH of your pool water? Watch your CSI level or you will get scale out of the returns.

 

[Pepperdinegal]

I purchased a CircuPool RJ60. My CH is at 375. We just had the pool replastered 40 days ago, so it’s obviously newly filled. Not sure how to mitigate the crappy hard water we have here in Vegas. Any suggestions?

Not sure what CSI levels are, can you please clarify?

 

[proavia]

I purchased a CircuPool RJ60. My CH is at 375. We just had the pool replastered 40 days ago, so it’s obviously newly filled. Not sure how to mitigate the crappy hard water we have here in Vegas. Any suggestions?

Not sure what CSI levels are, can you please clarify?

Water softener - whole house if possible. And plumb to your autofill.

 

[mgtfp]

CSI is the calcite saturation index. If too positiv, Calcium Carbonate (aka Calcite) will fall out of solution and create scaling. If too negative, plaster pools can get damaged.

With a SWG you want it slightly negative (between -0.3 to 0), because the pH within the cell will be quite high, to avoid scaling within the cell.

In the Pool Math settings, turn on "Track CSI" and "Track Temperature".

Your CH is still good, but if your fill water is hard, this will increase over time. Each time you replace evaporated water (leaving the Ca behind) with fill water, you add more Ca.

Would be good to test CH and TA of your fill water.

 

[Pepperdinegal]

We looked into a whole house softener about 5 years ago and the quote was upwards of $5k for our 5500 sq ft house. I think that using an RO truck every few years is probably a more viable option.

 

[Pepperdinegal]

So, it looks like to keep my CSI slightly negative, I need to get my TA down to about 50-60, especially with the temps creeping up and the fact that the new plaster is raising the pH constantly. Am I correct that I should use MA to lower the pH to 7.0 and then let it naturally rise to 7.6 and then lower to 7.0 again. How many times do I need to do that until I see a decrease in the TA? Is it a long process?

 

[Pepperdinegal]

Okay, I just tested my fill water and it’s as follows:
TA - 110
CH - 210

 

[mknauss]

We looked into a whole house softener about 5 years ago and the quote was upwards of $5k for our 5500 sq ft house. I think that using an RO truck every few years is probably a more viable option.

Monitor the pool water CH monthly. When you get near 800 ppm, time for a complete drain and refill.

How many times do I need to do that until I see a decrease in the TA? Is it a long process?

When your pH reaches 7.6-7.8, lower it to 7.2. Test TA every time you need to add acid. The TA value is needed in Poolmath to calculate how much acid to add. The TA will come down slowly. To speed it up, you need to aerate the pool water to force the pH up. To maintain TA you will need to add acid twice a week during all but the winter months.

 

[mgtfp]

Bringing CYA up to the recommended 80ppm for SWGs also helps a bit to keep the CSI down. CYA also acts as a buffer and adds to Total Alkalinity. When calculating CSI, TA is used to estimate the amount of Carbonate ions in the water, which together with Ca ions can form Calcium Carbonate.

Pool Math does this calculation from "Total Alkalinity" (TA) to "Carbonate Alkalinity" (CA) internally. You have roughly CA = TA - CYA/3.

That means having a TA of 100 with no CYA results in a CA of 100, all of the TA has to be considered to calculate CSI. But with a CYA e.g. of 90 (just to make the numbers easier), about 90/3=30 of TA is actually "CYA-Alkalinity", and the CA (which is the relevant part for CSI) is only 70.

That is a nice side effect of keeping CYA a bit higher with SWGs. Take that into consideration and play around a bit in Pool Math to find the workable range for you.

 

[Pepperdinegal]

So, would you all recommend not adding my salt and turning on the system until I have my TA down to 70-80 and CYA up to 80?

 

[mknauss]

So, would you all recommend not adding my salt and turning on the system until I have my TA down to 70-80 and CYA up to 80?

No. You can do it all at the same time.

 

[mgtfp]

It's fine to add the salt now, even if you decided to turn on the SWG later (salt reduces CSI, by the way). Bring CYA and salt to target (don't forget to adjust FC to the new target). Then work a bit on your TA and turn on the SWG once CSI is more reasonable. The lower TA will also keep pH rise down.

What's your water temperature?

 

[Pepperdinegal]

Would there be harm in turning the SWG on once pH and FC are in order and then continually work on the TA? Pool temp is currently 66 degrees. It looks like if I can get my TA down to 120 over the next 48 hours, my CSI would be -0.08.

 

[mgtfp]

The effect of CYA between 60 and 80 on CSI is not huge, but the difference between 30 and 80 is quite noticeable. But towards summer you will want it up to 80 in Las Vegas anyway. And then it will help a little with CSI.

After your first pH reduction down to 7.2, your TA will already be down by about 10. If you then bring pH back down to 7.2 once it gets back above 7.6, you are already keeping CSI in a more reasonable range. Once TA is down where you want it, you can let pH drift up to 7.8 again, where it might likely like to stay once TA is lower.

So, as Marty suggested, you can work pretty much simultaneously.

Depending on how much evaporation you have to replace with fill water, it will probably settle down to more or less frequent acid additions to keep pH and TA in check, and therefore CSI. Until CH gets unmanageably high and you have to replace at least some water to get CH down again.

Or install a water softener for the regular water top ups. But it might be worth observing for a while before going down that path.

 

[Pepperdinegal]

Sounds good. I have another gallon of liquid stabilizer I can put in tomorrow after I test. Pool math called for 4, but I wanted to be conservative and only put three in. That took me from 25 to 60 in about 8 hours. I think I’ll work on the TA for the next 2-3 days and then once it’s down to 120 I’ll go ahead and add the salt and get the generator going. I’ll continue to work on the TA and hopefully in another 2-3 weeks it’ll be down to where I want it. With new plaster and a spa spillover, I think I just need to come to terms with needing to add acid at least once, if not twice per week this summer.

 

[mgtfp]

Be careful with liquid stabilzer. Often all the CYA settles in a sludge at the bottom, and when adding only a partial bottle, you might add mainly water. And when adding the rest of the bottle you get a lot more than planned. Granular stabilizer is easier to dose. Just my opinion.

Since you just brought CYA up to 60, I would wait at little before adding more to avoid overshooting.

 

[mgtfp]

once it’s down to 120 I’ll go ahead and add the salt and get the generator going.

You can add the salt in parallel. And as Marty already mentioned, it makes sense to first only add 2/3.

Before starting the SWG, you have to make sure that the salt is fully dissolved, therefore I'd start adding salt straight away.

 

[Pepperdinegal]

I’ll go ahead with the salt tomorrow. How long does it typically take to dissolve? Will I know bc I won’t see it anymore?