Calcium Hardness Levels for SWG, Fiberglass Pool

[cmacowski]

I'm opening up my pool for the season, and I have all my levels set, except for my calcium hardness.

Current CH reading is 180.

I've read varying theories on how important this level is. I have a SWG, fiberglass pool (Corinthian 14 - Latham Pool) and an electric heater.

PoolMath is telling me I need to target 350 CH (meaning i should add 13 lbs of calcium chloride) but, again, reading lots of conflicting theories on the importance here, given my pool is fiberglass and has electric heater.

All my other levels can be seen below:

FC - 7.5
TC - 7.5
CC - 0
PH - 7.3
TA - 70
CH - 180
Salt - 2900 (but this will likely go up...my electronic reader usually takes a few days to register the proper salt level)

Ultimately, I don't want to unnecessarily add more chemicals to the pool if I don't need to.

Any advice would be greatly appreciated.

Thanks!

 

[duraleigh]

I would leave everything alone. Depending on the CH of your fill water (and rainfall) CH will slowly increase and I have yet to hear a really good argument for fiberglass pools even needing CH.

 

[cmacowski]

Ok thank you!

Just one thing to note, I didn’t need to actively fill the pool when I opened it. I have a mesh winter cover and it just so happened that the amount of rain water that came through made it so the pool was already at the right level.

 

[Texas Splash]

Remember, the Poolmath APP lists a recommended CH of 350, but if you go to the TFP Recommended Levels page you'll see a minimum CH of 250 for FG. You're below that but are probably fine. Technically FG pools don't require calcium as they are not made with plaster products, but TFP established a minimum CH umber (250) as a baseline to cover a wide variety of pool owner situations such as water quality/staining, potential plaster products like a waterline tile, heater, etc. Unless your heater manual calls for a minimum CH level or you have a waterline tile, your CH is fine. The APP simply doesn't know all the specific details of your pool. That's why it's good you post here and ask the forum.