Is my water leaching calcium out of my PebbleTec surface?

SwimmingInFlorida · Postby **SwimmingInFlorida** » Sat 28 May, 2011 09:32

Greetings everyone -

I had my 14000 gallon below-ground pool resurfaced with PebbleTec about 3 weeks ago. I have been testing the water at least twice a day and trying to keep it balanced. These are the most recent readings (from this morning):

1 hour ago:
FC: 2.45
TC: 2.65
pH: 7.5
TA: 101
CH: 162
CYA: 49

Last night, I added 2c muriatic acid and 2 tabs (3-inch)

24 hours ago:
FC: 1.68
TC: 1.80
pH: 7.7
TA: 108
CH: 172
CYA: 49

My pool: 14000gal, non-salt
Pool chemicals: Trichlor tabs, muriatic acid, sodium bicarbonate, cyanuric acid, 1-lb calcium hypochlorite (73%) shock treatment (powder package)
My pump & filter: 2.0HP constant speed, cartridge filter

To cut to the chase, after muriatic acid and sodium bicarb were initially added to the new water, I started adding a bag of chlorine shock about every other day, because the chlorine would always drop to 0 within 24-36 hours. (I goofed and added chlorine before the pH and alkalinity were stabilized because I didn't know any better at the time.) I was also adding anywhere from 2-4c of muriatic acid per day to repeatedly bring the pH down from 7.8 to around 7.5. After the first 10 days, I added sodium bicarb to bring Alkalinity up from 90 to 110. I have done nothing to adjust Calcium Hardness.

Now that my test results are becoming a little more "stable" I'm adding less muriatic acid (a cup or two every 3-4 days) and I'm running with chlorine tabs which seems to be raising my chlorine about .5ppm every 12 hours. (I have my tab feeder on the highest setting.)

The water is sparkling clear with no odors, though it does get a bit cloudy after swimming and after brushing the surface.

Okay, so now my question/concern: I'm reading The Ultimate Guide to Pool Maintenance, 3d Ed by Terry Tamminen which states I should bring my Alkalinity up to 120ppm and my Calcium level up to 200-400ppm to keep the water from leaching the calcium out of my surface. I'm worried that, although my current numbers are within normal range, it might be because my PebbleTec is dissolving? (Okay, I'm being a bit paranoid, perhaps due to the cost of the surface.

)

Am I doing okay or should I bring my Alkalinity and Calcium Hardness up to the book's recommended levels?

Thank you!

Postby **czechmate** » Sun 29 May, 2011 08:37

You can easily let the PH rise to 7.7.
Use the POOL CALCULATOR to check your CSI. its perhaps the most important test in any gunite pool.
The CSI will change with rising temperature, so keep that in mind.
Any new surface will release calcium from the surface 6 months to a year.
You have a nice CYA level, so try to limit its rise with switching between Trichlor and Cal Hypo, if you do not want to mess with a liquid bleach.

SwimmingInFlorida · Postby **SwimmingInFlorida** » Fri 03 Jun, 2011 11:04

Thanks for your helpful reply!

I will certainly refrain from adding any CYA. I plan to alternate between lithium hypochlorite and bleach for sanitizer.

So, even though my Calcium Hardness is 162, should I leave it alone, counting on it going up by itself in the first 6-12 months as the surface releases calcium? Or should I "protect" the surface by increasing Calcium Hardness to 200-250 so that it doesn't take so much from the surface?