CH Question

[Rebel-Redbird]

Latest test results, after following Pool Math guidance and the Taylor-2006 kit:

FC: 4.8
CC: .4
Ph: 7.4
TA: 150 (down from 170 a few days ago)
CYA: 80
CH: 120
Salt: 3600

So, I guess I’m curious about Calcium Hardness. I don’t have any metal in/near my fiberglass pool and there is no concrete in contact with the water to leech. PB told me during pool school (seemed like his personal opinion) that since it’s fiberglass I shouldn’t really worry about CH. He was even recommending keeping it low to prevent scaling on the SWG.

Should I raise it, or am I fine? Am I missing something like....low CH will eventually cause water to corrode metals in my heater or something?

Thanks for a CH reality check if that’s incoming!

 

[YippeeSkippy]

Do you *have* a heater? Some do require a certain amount of calcium to be in the water, others not.

So have you tested your fill water? Mine here in my part of Georgia is quite soft with only about 40ppm of CH, but folks out in the west are often pulling tap water with 400ppm and really have to learn to deal with it!
Unless we know what your fill water source water tests out can we determine if your 150ppm is unusual?

Here at TFP we have come to the understanding that some calcium in a fiberglass pool is fine to have, perhaps even a good thing?? Your level is neither high nor unusually low so I would not worry about it in the least.

Remember that during warm/dry weather when water evaporates, the calcium will remain in the pool and over time your CH level will actually increase. The only way to lower CH is to replace water with fresh low calcium water or perform a certain rare treatment to it called Reverse Osmosis. Kind of like dialysis for pool water, y'know?

Maddie

 

[Rebel-Redbird]

Good call, just tested the source water and it’s 80ppm, so looks like we have pretty soft water?

I do have a heater, Pentair MasterTemp 250,000 so I’ve added that to the ‘ol Signature.

You know, the PB was talking about the fact CH will rise as the season goes on, simply slipped my mind just now. He said if I raise it now I’ll be kicking myself in the summer when I’m draining/filling to lower it.

I think that’s why I didn’t stress about the 150ppm at this time....but I just wanted to make sure there isn’t anything -wrong- with keeping it as is since the Pool Math app recommends 220ppm minimum.

Appreciate the feedback!

 

[YippeeSkippy]

Please review your heater's manual for their required level of calcium. You should use that as a guide in this case.

Maddie

 

[Leebo]

Some heater manuals may say that a level is needed, but it’s a bogus claim. Having a low level of CH in a heater won’t harm a darn thing.

As for your fiberglass, that’s a bit more tricky. There are some fiberglass manufactures that may use calcium carbonate in the gelcoat of their pools. If yours happens to have used calcium as a filler, and you maintain a low CH level, then in theory your soft water could pull CH from parts of your pool. If however your pool manufacturer didn’t use calcium carbonate, then having a low level won’t harm anything.

 

[YippeeSkippy]

Getting that information from the fiberglass pool builder hasn't been very easy in my case, I have to say. I do add Calcium to my pool in such an amount that I'm safe either way. Not so much to risk a problem, not so little either especially since my fill water is so soft.

But warranties on heaters need to be taken into consideration also. If the manual says have x amount, *I'd* have close to that.

Maddie

 

[Rebel-Redbird]

But warranties on heaters need to be taken into consideration also. If the manual says have x amount, *I'd* have close to that.

Maddie

Good call on the heater parameters. Just looked up the MasterTemp 250 and 150ppm is minimum, 200-400 ideal. Looks like I should probably bump to 200 understanding that CH will rise as evaporation occurs.

I looked up the user guide for Leisure Pools, and they recommend a calcium hardness of 350. So should I bump CH to 350, or will I regret that decision as it rises naturally? Rather not get into a cycle of constantly bumping CH and then replacing with new water to keep it 350-400ppm, but maybe I should?

 

[Richard320]

Good call on the heater parameters. Just looked up the MasterTemp 250 and 150ppm is minimum, 200-400 ideal. Looks like I should probably bump to 200 understanding that CH will rise as evaporation occurs.

I looked up the user guide for Leisure Pools, and they recommend a calcium hardness of 350. So should I bump CH to 350, or will I regret that decision as it rises naturally? Rather not get into a cycle of constantly bumping CH and then replacing with new water to keep it 350-400ppm, but maybe I should?

You'll need to decide that for yourself. Just know that it's not terribly hard to maintain a decent CSI up to 800 CH.

I don't know what I;d do. I suffer from hard water and skyrocketing CH, so I'm biased against raising it. But I also see where it might be prudent to get CH up to manufacturer's recommendations -- and have it tested and documented -- in case there are problems down the road that involve lawyers and such.