Calcium hardness too low

[looch21]

Hi
I’m new to testing pool water (abs owning a pool). Heeded the advice from this fab site abs bought a test kit. The results are FC=2, CC= 0, pH = above 7.8 (think it’s about 8.0- expected this as the auto acid .doser isn’t working) CYA = 30, TA=60, CH= 200.
I’ve dosed it manually with acid and brought ph down to 7.7. The pool math app tells me to add almost 12 kg of calcium chloride. This seems really excessive. Any advice greatly appreciated. It’s a 40000 litre fibreglass SWG pool. Pump runs 10 hours a day.

 

[Texas Splash]

G'day and welcome to TFP! So just remember that with a FG pool, your CSI level and/or CH really shouldn't matter. Unless you have a tile waterline, there is no plaster that can erode from aggressive water. Also keep in mind the PoolMath APP may provide some general recommendations, but may not know everything about your situation. While an ideal CH may be around 350, a CH of 250 is still fine. Sure, 200 is slightly low for a plaster pool, but an elevated pH compensates for that. But again, you have FG, so a CH of 200 is plenty. No worries.

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

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[MA5177]

My fill water is also about 200, I'm going to leave it alone because it will be rising on its own with adding water

 

[looch21]

We generally have ‘soft’ water in Melbourne so adding water probably won’t wont raise the Calcium hardness levels.

 

[looch21]

G'day and welcome to TFP! So just remember that with a FG pool, your CSI level and/or CH really shouldn't matter. Unless you have a tile waterline, there is no plaster that can erode from aggressive water. Also keep in mind the PoolMath APP may provide some general recommendations, but may not know everything about your situation. While an ideal CH may be around 350, a CH of 250 is still fine. Sure, 200 is slightly low for a plaster pool, but an elevated pH compensates for that. But again, you have FG, so a CH of 200 is plenty. No worries.

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

Thank you Texas Splash. This is super helpful. I do have travertine copers and paving around the perimeter of the pool so I suppose I run the risk of Ca leaching out of these. They cost a pretty penny so I’d rather avoid. I think I will add a kilo of Calcium hardness, wait a day or two and retest before adding any more. I’m in Melbourne Australia where we typically have ’soft’ water - so there’s very little of it in the water supply anyway.

 

[YippeeSkippy]

Water stuck behind coping/tiles is what causes calcium to leach up and out. Its called efflorescence.

Efflorescence - Further Reading

www.troublefreepool.com

Sidenote: Being in FL, I would suggest you raise your FC level a bit more to allow for loss so you don't bottom out and risk algae.
Here are the recommendations ( I always go 1-2 over as added protection)
Recommended Levels

Do you have a GOOD test kit....one with an FAS-DPD powder test for FC/CC?

Maddie