Add Cal-Hypo?

[dlduvall]

My question: If I need to shock when opening my pool AND I need to raise my CH level, would I be better off to use the store "shock" products? Cal-Hypo would do both, wouldnt it? Or would it not be fast enough? My opening CH level was 200 and I know it has to be at least 250. Started with 0 chlorine also.
Full set of numbers:
PH 7.5
TA 100
CYA 50
CH 200
TC 0

Just wondering, have to make a trip to WalMart anyway! :-D Thanks!

 

[duraleigh]

That's not a bad plan. YOu could even use Cal Hypo as your chlorinating source until you got your CH up a little.

Jason's calulator will give you the dosages if you choose that route. The money you save and the convenience you get may be offset a little by Cal hypo not dissolving as quickly as you'd like.

That said, I have done exactly what you are contemplating and used it as my chlorinating source for about 30 days until my CH reached 250. I got a little calcium precipitate on the clear strainer basket lid but that was about the only issue.

 

[Guest]

It would work but would take several pounds, the exact amount depending on whether it's 48%, 65%, or 73% cal hypo. The easiest way to figure is by how much you raise the FC. For every 10 ppm FC added by cal hypo you are also adding 7 ppm calcium so to get about a 50 ppm rise in the calcium you would need to add 70 ppm FC over time. If you are raising your FC 12 ppm over your base FC level each time you add cal hypo to shock you would need to shock about 6 times to raise your CH by about 50 ppm. It's not exact but it's close enough for government work!

 

[dlduvall]

Thanks for the quick responses, guys! Good to be reassured that I am slowly starting to learn this stuff! My hubby isnt totally convinced yet that I know what I am doing, but slowly I'm winning him over!