Help, large Calcium spots keep appearing and growing.


Bronze Supporter
May 20, 2016
North Augusta, SC
I have a 15,000 gal SWG pool that was built early 2017. Besides the initial start up I only add acid and liquid bleach in the colder months. I use the TFP kit to test my chemicals.

Current readings.
FC 4
CC .5
CH 400
TA 80
And PH likes to stay around 7.8

How do I get rid of these spots and do I need to lower my CH?



Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
Laughlin, NV
Those look like calcium nodules. Are they raised up from the surface of the pool?

Do a Search for Calcium Nodules. Review those threads and see if what you have is similar.


Gold Supporter
TFP Guide
Jul 21, 2013
Northern NJ

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