Calcium Deposits?

[Jasheon]

WoW, i am filling this forum up with my posts.... :D.

Anyways, I have always kept my pH levels on the low range in Salt water pools, I have been told to keep it at 7.1 range and I do that.

But i am having a problem with what it looks like Calcium deposits are that developing on the walls of some of my dark bottom pools. I take care of every single pool the exact same, and some dark bottom pools do not have it but others do. I have been taking care of a pool for nearly 2 years then out of the blue these calcium deposits started showing up. I can brush them off with a wire brush or a pumice stone and they come right off. But they keep appearing a week later. I have taken a few pics and curious to hear what you guys have to say.

They mostly develop in the spa (the spa is connected to the pool) then they start going into the pool itself.

http://i35.photobucket.com/albums/d177/Jasheon/Picture011.jpg
http://i35.photobucket.com/albums/d177/Jasheon/Picture010.jpg
http://i35.photobucket.com/albums/d177/Jasheon/Picture009.jpg
http://i35.photobucket.com/albums/d177/Jasheon/Picture012.jpg
http://i35.photobucket.com/albums/d177/Jasheon/Picture008.jpg


Chemical readings (Salt Pool)

FC 4.5
pH 7.3
TA 79
CH 240
Cya 85

I have been told that I need to keep the CYA levels between 60 -80 is that right for salt generators?

Thanks

[Jasheon]

I even went to the extreme and back washed the spa into the pool and acid washed the spa some, took all of the deposits off but they came back a few weeks later. :\

I only did this twice, i know acid washing shortens the life of the plaster.

[PoolDoc]

I'm gonna email a guy who recently registered, and who knows WAY more about this than I. Maybe he'll answer. Or not. He manages a pool route with over 10,000 pools.:eek:

Ben
"PoolDoc"

PS: there's not a simple answer to this problem!

[Jasheon]

The pools that have this problem were all built by the same builder. Something tells me it's the way they mix the calcium to make the plaster. Just a shot in the dark though.

[waterbear]

The pools that have this problem were all built by the same builder. Something tells me it's the way they mix the calcium to make the plaster. Just a shot in the dark though.

possibly calcium nodules
http://www.poolhelp.com/onBalanceCalciumNoduleBulletin.pdf

[PoolDoc]

Yeah. Poolhelp is Que's site -- he's the guy I mentioned above.

Ben

[Jasheon]

Very very interesting, this might just be the problem I am seeing. I should try and email him the pictures and see what he thinks. I wish he had some better pictures. I will try and take some better pics but its hard for them to come out right since they are under water.

I did not read on how long it takes for the calcium nodules to start showing themselves though. You would think they would show just a few months after the pool is built. I ave seen it take as less as a year to appear and in 1 case 3 years.