Getting SWG pool levels under control plus pic of soft stone

[Lpearson15]

This is my first post and I'm so appreciative of your expertise and the friendly community!

I decided to stop having my water tested at X pool store and buying their chemicals. I bought the suggested Taylor kit and have read a lot of posts on this site. I have learned so much!

We never got a good lesson on caring for a salt water pool. Our pool is 9 years old. We were told to only worry about the PH and salt level. We cover the pool in the winter and it runs at 1300 rpms 24 hrs a day just to move the water. Unfortunately, we let the PH stay high and never had the water tested so I have scaling, stains and etched plaster. I'm looking at new plaster or acid wash at the least this Fall. Thought maybe this would be a good time to learn about caring for a salt water pool.

Pump runs 1300rpm for 1 hour to start pool
3125 rpm for 5 hours in the morning. Run Polaris for 1 HR during this time. Some days it's doesn't need to run at all.
2750 rpm 4 hrs during afternoon
Trying to reduce electricity demand During the day. Used to run 3125 the whole time.

Currently my #'s tested at 5:00pm today, water temp ~88-90.
FC 6.5
PH 7.6
TA 70
CH 310....keep putting calcium chloride in, hard to raise
CYA 80
BOR 10..... Just got the kit and will buy Boric acid soon.
Salt....that's the problem. Taylor kit shows 3800? Tested twice. Maybe it's a fluke? My display reads 3100. I have not added salt since mid May.

So, I could use some tweaking. Emptying the pool of water to lower salt is not an option right now. I have to top it every other day due to evaporation. I'd like to change the pump schedule/rpm if possible to lower cost.

Also, and this is for folks who are in the planning stages of building a salt water pool. DO NOT get Oklahoma flagstone. It's too soft! I don't know if we got sold or this issue was just becoming known when pool builders were building salt water pools 9 years ago.I have sealed the stone 3-4 times in 9 years. 3 years ago we started rinsing the pool deck after swimming. I can't even enjoy my pool b/c when the kids run across the flagstone it flakes off into the pool! I sit there watching the saltwater dry on it in the hot sun. I want to hose the deck with each splash but I end up screaming silently while they play. So I took a putty knife to the loose flagstone before sealing it once again(the pic). I'll be replacing this along with the plaster. Not happy.

 

[Schadenfreude]

Your numbers look really good to me.

I wouldn't worry about that salt level unless it is higher than the manufacturer's recommended maximum level.

Your flagstone sucks, but that is probably not because of salt in your pool.

 

[pooldv]

Welcome to TFP!

That flagstone would look like the with salt or not. I have flagstone around the pool that is fine starting season 5 and I have flagstone in the yard that is doing the same as yours and is nowhere near the pool. My PB did a good job of picking dense, non-flakeable flagstone for the coping. Most of ours looks the same as it did day one.

If your SWG isn't giving you a high salt error then don't worry about the salt level.

Now, the Scaling is definitely a water management issue. Our water has a tendency to scale. It is important to manage the CSI. Enter all, all, test results into PoolMath and it will calculate your CSI score. Keep that number between -0.3 and 0. Tweak PH, TA and CH to change the number. Salt, temp and borate also affect CSI.

More here, Pool School - Calcium Scaling

 

[Meadow]

OP, you're not alone! The flagstone on ours flakes off too and I hate it! Much worse, the edges can get really sharp and more often bathers wind up with scratches and cuts.

I ruled out salt as the culprit because ours was built in 2000 and I just installed the SWG yesterday.

 

[ping]

Welcome to TFP!

Your pool does not need any more calcium.

You do not need boric acid either as it is optional. What is your reason for wanting to add it?

Have you removed the cell to see if it has scaling inside it?

You can cut way back on the time you are running the pump. My suggestion is to run it 7 hours a day at 1000-1300 RPM and 1 hour at full speed for the cleaner. You will need to adjust the SWG % up to accommodate the shorter pump run time.

Determining Pump Run Time
Water Balance for SWCGs

 

[Lpearson15]

I sealed my flagstone yesterday and I happened to notice how fast the stone absorbed the sealer so, unfortunately, it will have to be replaced b/c I will never be able to get enough sealer on it to save what is left.

I wanted to add borates to stabilize the PH. several factors make it rise so easily. And since I didn't manage it very well for the first 8 years I have stained and pitted plaster. I didn't think about checking the cell for scale so I will do that today and well as cutting back on pump time. Anything to bring my utility bill down!

Calcium:
I thought my CH was low at 310 so I went to the pool store to get Calcium Chloride to increase it but the sales guy actually talked me out of buying it! Said 310 was fine. Their recommended range is 200-400. Per the water balance on this site for SWG it shows 350-450. With a SWG what is considered too low?

 

[Jimrahbe]

I agree with the others.. this is a stone issue, not a salt water issue. My daughter has a pool which had Flagstone before we installed the SWG. You could just look at the stone and pick out the "bad" ones. The SWG has been running a little over a year and the bad stones are still bad, and the good stones are still good.

I live in Bedford, on the other side of DFW than you, but not all the far from you weather wise. I'd be worried if I had to top off my pool every other day, like you say you have to do. I suggest you do the bucket test to confirm if you have a leak or not.

Thanks,

Jim R.

 

[pooldv]

These are all good ideas and we can help you with all of it.

Borates, you should lower your TA down to 60 first.

CH at 310 is ok, keep an eye on it and see if it trends down or up over time. Mine has been dropping the last two years since we started getting so much rain. The years of drought before that it was climbing and got up to 450. I would say 250 is the lowest it should go.

 

[Lpearson15]

I should say I will be topping it more often now that it's going to be hitting 100+ soon. Also, my son and his friends splash out quite a bit of water when they play which causes me to add water regularly.

I'll watch the CH and keep a log. I appreciate all the help!

I find the responses about the flagstone very interesting. I wish I had done more research about stome options when we built the pool in 2007. Lesson learned!