New Pool Stone - Calcium or Efflorescence

[JMPool99]

New pool owner here -- just finished construction a few months ago. I'm trying to determine whether the white stains on the natural stone of the raised spa around the spillway are calcium or efflorescence. The spillway from the spa shoots into the pool, but there is some small dribbling of water that happens at the corners that gets onto the stone all day when the pump is running (if that makes sense).

My water chemistry is all in the standard "normal" ranges. We do have hard tap water where we are in California (if that matters).

Depending on whether it's calcium build-up or efflorescence would love some advice on how to control or clean. I've read a little in other TFP post about using muratic acid. Wasn't sure if that was safe if it gets into the pool water and how well that will work.

Thanks all!

 

[Texas Splash]

Based on the light haze texture of those stains, I'm leaning more towards it being residual hard water residue from the spillover when the water dries. If it were efflorescence, I would be looking for more definitive indications of moisture exuding from between those stones and perhaps more dripping marks. No doubt the local hard water, coupled with warm ambient temps (evaporation) plays a major role.

You mention your chemistry being in "normal ranges", but we don't see your water testing linked from the PoolMath APP to your TFP profile, so you might consider linking those test results and posting some recent results. Your signature is still blank as well not listing you pool and equipment info or how you test your water. All of this info could help with future responses.

As for the muriatic acid (MA), it's the #1 way to control pH/TA, so whether you add it directly to the pool for chemistry or make a spray mixture of MA-to-water in a 1-4 ratio to spray on the stones, it's perfectly safe. Just be careful of the spray if it's windy and take precautions to protect your eyes and exposed skin. You can apply some MA to the stones and perhaps gently brush as well. Rinse once complete.

Efflorescence - Further Reading

www.troublefreepool.com

 

[JMPool99]

Thanks for the reply - really helpful. Leslie's was pushing some descale solution for cleaning stone and to help maintain the pool before I tried MA.

Good tip on the PoolMath app -- I just grabbed it. I've had a chlorine (high) issue the last month that pool guy (same as start-up guy) said he was addressing. Here are the recent figures.

Today
FC 5.6
pH 8.2
TA 43
CH 210
CYA 116

1 month ago
FC 12.9
pH 7.4
TA 45
CH 260
CYA 104

4 months ago (only a couple weeks old)
FC 7.0
pH 7.9
TA 111
CH 172
CYA 36

Leslie's also detected some copper in the water (0.3) that wasn't there three months ago.

 

[AQUA~HOLICS]

Natural stone is porous and you are going to be dealing with this situation from now on, only question is at what level. You may want to look into this product as a maintenance way to keep this under control.

 

[JMPool99]

ScaleTec looks like something you add to the pool - correct ? Not to directly apply to calcium?

Every heard of the mPulse? Pool guy was pushing this.

Deep Blue Water Technologies mPULSE 3000 Pool Water Calcium Treatment System | MP3001

Pool Supply Unlimited has some of the best prices when shopping for Deep Blue Water Technologies mPULSE 3000 Pool Water Calcium Treatment System | MP3001

www.poolsupplyunlimited.com

 

[Texas Splash]

ScaleTec looks like something you add to the pool - correct ? Not to directly apply to calcium?

That is correct. I don't see much benefit to using such products. With proper testing and water management, you can maintain a proper "CSI" level (slightly negative) to prevent scale in a pool. But that's different from the water spray and evaporation from a spillover. Speaking of testing, be very cautious about the pool store tests. They are most often wrong. That is confirmed by some of those numbers posted above that have fluctuated significantly. Ask Santa to get you a TF-100 or Taylor K-2006C test kit, and get a magnetic speedstir as well. You'll be glad you did.

If you are using chlorine tabs, it's best to stop and switch to liquid chlorine. Tabs increase the CYA quickly and are also acidic which tends to lower pH and TA. Liquid chlorine has next to no side effects and is much more predictable. Copper typically gets in the water from bad pool store products or an eroding heater core. TFP recommended levels and chemicals are proven safe, effective, and wont cause problems when used properly.

Pool Care Basics Archives

Your one-stop shop for all things TFP to include: ABCs of Water Chemistry, Recommended Chemicals/Levels, Test Kits, Troubleshooting, and much more!

www.troublefreepool.com

 

[Bperry]

If the pool store numbers are to be believed, your FC last month wasn’t that high given that your CYA level was definitely high. Check out this article.

The Free Chlorine and Cyanuric Acid Relationship

Managing your cyanuric acid and Free Chlorine levels is key to stabilizing your pool. Learn how these two items affect each other.

www.troublefreepool.com

 

[JMPool99]

Looks like my pool guy had about 5 tabs in the floater -- that likely explains the CYA -- I need to just stay on liquid as everyone has said!

@Bperry - Thanks for the chart. though it does say those those high CYA and FC are "* Not Recommended"

 

[Bperry]

Looks like my pool guy had about 5 tabs in the floater -- that likely explains the CYA -- I need to just stay on liquid as everyone has said!

@Bperry - Thanks for the chart. though it does say those those high CYA and FC are "* Not Recommended"

Yes it does. That’s because it gets harder and more expensive to maintain that FC level. You’de be better off at a lower CYA level which would allow a lower FC level that’s cheaper to maintain.

 

[JMPool99]

I have a chlorinator -- does anyone here think I would be better off switch to salt? I held off because my decking (Even with the low salt content) would likely need to be sealed.

Also, are their digital devices for taking readings of levels?

Thanks for all the tips. I'm learning!

 

[Texas Splash]

An SWG sure is convenient, and many believe the increased salt level of the water feels a bit more softer to the skin. With chlorine supplies in shortage around the country, SWGs have come-in handy. There are digital pH meters, but they have to be calibrated. The TF-100 or Taylor K-2006C drop test kits continue to be the foundation of reliable water testing.