Opened pool to calcium deposits

Total hardness and calcium hardness in pool water.
Scale, calcium buildup, hard water and scaling problems.
momstime
Pool Newbie
Pool Newbie
Posts: 4
Joined: Sat 25 Apr, 2009 16:12

Opened pool to calcium deposits

Postby momstime » Sat 25 Apr, 2009 16:20

First post and I hope someone can help me...

We had our gunite pool with a SWG installed in the fall of 2006, just in time to have it closed for the winter.

In the spring of 2007 we opened the pool to find the walls and bottom coated in calcium. We spent most of the season scrapping and brushing to no avail.

Closed the pool in the fall.

In the spring of of 2008, we had a pool company drain our pool and lightly sand the entire pool surface like new. We spent the entire season maintaining a diligent focus on our chemistry...with a huge effort on PH and calcium. We kept everything perfect all season long and closed the pool in the fall.

Just today (2009) we opened the pool to find that it is once again coated in calcium!!!! My hubby is having a absolute fit wondering if we are going to have to drain and sand our pool every year (at a cost of about $800).

Can anyone offer any advice and help??? I am desperate in Michigan.


Pooltech32
Swimming Pool Wizard
Swimming Pool Wizard
Posts: 75
Joined: Thu 06 Jul, 2006 20:43

Opened pool to calcium deposits

Postby Pooltech32 » Sun 26 Apr, 2009 21:57

what do you mean when you say you closed the pool? If you keep water in it, you need to keep an eye on your PH, Salt pools will run a very high PH if left for any amount of time, this will cause scale. You need to keep the PH down ALL winter with the pump running if possible.
Pool repair guy
momstime
Pool Newbie
Pool Newbie
Posts: 4
Joined: Sat 25 Apr, 2009 16:12

Opened pool to calcium deposits

Postby momstime » Tue 28 Apr, 2009 09:29

I live in Michigan. I drained my pool below the filter intake valves...about 1/4 of the pool water, blew out my lines, added antifreeze and capped the ends, winterized my pump/pool equipment with a winter blanket and covered the entire pool with a mesh safety winter cover that is pulled tight by steel springs. Everything is off on the pool and I'm pretty sure that with our sub zero winters that seem to last forever that my pool was a solid block of ice...or partial ice at the least. On top of that, there was about 2 feet of snow on top of the cover most of the winter. Most of my neighbors have pools and we all do the same thing. In March or April we begin the process of opening the pool for the season.

Do you know of a better way to deal with my pool over the winter? I'm open to suggestions.
Pooltech32
Swimming Pool Wizard
Swimming Pool Wizard
Posts: 75
Joined: Thu 06 Jul, 2006 20:43

Opened pool to calcium deposits

Postby Pooltech32 » Tue 28 Apr, 2009 17:56

No we don't have to deal with cold cold winters here in Vancouver BC, is the calcium only where the water is?
Pool repair guy
Me...
Swimming Pool Superstar
Swimming Pool Superstar
Posts: 302
Joined: Thu 26 Feb, 2009 11:11

Opened pool to calcium deposits

Postby Me... » Wed 29 Apr, 2009 10:15

Be interesting to see a complete chemical test result from the fall.

Pooltech32, don't ruin the vision. Lots across the border still envision Igloo cities up here I think :lol:

And I do remember a time when the pool became a nice backyard skating rink.
Pooltech32
Swimming Pool Wizard
Swimming Pool Wizard
Posts: 75
Joined: Thu 06 Jul, 2006 20:43

Opened pool to calcium deposits

Postby Pooltech32 » Thu 30 Apr, 2009 00:14

my brother lives in a Igloo, just a few hours nprth from me :lol: I am lucky I guess. I think that Chem Geek could maybe help out more than me on this one.
I am thinking though. sometimes depending on the builder they use tons of calcium in the concrete foundations of a pool and the plaster to help it set up faster, this can cause some issues with calcium, I actually am having an issue with a brand new pool we just got, on 1 side of the pool it had different concrete used on the coping than the other side, the one side looks like a brand new pool and the other looks like a 40 year old pool with tons of calcium leaching out from behind the tiles, maybe there is a connection?
Pool repair guy
chem geek
Pool Industry Leader
Pool Industry Leader
Posts: 2382
Joined: Thu 21 Jun, 2007 21:27
Location: San Rafael, California

Opened pool to calcium deposits

Postby chem geek » Thu 30 Apr, 2009 01:01

I'm with Me... in that a chemical test before and after the closing would really help narrow down what's going on. Normally you don't get much change going on in a pool that's closed except that the zero chlorine can lead to algae growth when the water warms up and to bacteria growth that sometimes converts CYA into ammonia. With heavy calcium, that means that one or more of pH, TA, CH got high.

Maybe, just maybe, the pool was closed with the TA being high so over the winter the outgassing carbon dioxide caused the pH to rise, but it sounded like the pool was frozen. If there was a lot of evaporation and refill with water high in TA and CH, then that could cause problems, but again, the pool was frozen much of the time.

momstime, did you do any water testing just before closing and just after opening the pool -- if so, do you remember those results?

Richard
momstime
Pool Newbie
Pool Newbie
Posts: 4
Joined: Sat 25 Apr, 2009 16:12

Opened pool to calcium deposits

Postby momstime » Fri 01 May, 2009 15:07

Yes, tested religiously. Actually I think my pool IS my church during the summer season. LOL
Anyway, when we closed the pool the readings were...

TA 150
PH 7.2
Calcium hardness 100
CYA 40

We boosted the Free Chlorine to 5-10 at closing.

I know the rain and melting snow really boosts the PH, but I don't know what to do about that over the winter. I can't add acid to a stagnant pool that is partially frozen.


The good news is, for anyone else suffering with this condition, I was able to drop the PH to around 7.0 and sand the scale off the bottom of the pool. Thankfully the scale was not on the walls this year..just the bottom (75%) It took tons of elbow grease, but it is almost back to completely smooth. Now, I just need to figure out how to avoid this for next year. My dh thinks it is the salt system and he does not want to use it this year. Is he right?
momstime
Pool Newbie
Pool Newbie
Posts: 4
Joined: Sat 25 Apr, 2009 16:12

Opened pool to calcium deposits

Postby momstime » Fri 01 May, 2009 15:16

I'm a dork....I should have typed
TA at 80. My bad!
Me...
Swimming Pool Superstar
Swimming Pool Superstar
Posts: 302
Joined: Thu 26 Feb, 2009 11:11

Opened pool to calcium deposits

Postby Me... » Fri 01 May, 2009 15:48

Seems odd for sure. With those readings if anything the Calcium would be on the low side. What was the Salt reading? Not sure if extremely high salt readings and very high TDS could result it this happening.

Any idea what the finish on the pool is? If in the fact the entire pool was brand spanking new in 2006 then possibly for a year or two the non-circulation could contribute to very high pH right at the wall and floor.

Return to “Hard Pool Water & Scale”

Who is online at the Pool Help Forum

Users browsing this forum: Google. [bot] and 0 guests