Double check my dichlor

pool mum

Well-known member
May 31, 2013
Setting up my hot tub for the first time - please double check my amounts. I want to bring my CYA up to 30. According to the pool calculator, on my 420 gallon tub, I need to add 3 oz dichlor which will give me 27 CYA (close enough), and will bring my FC up to 30. Does this sound right? That seems like a really high FC for such a tiny amt of product.

If this is accurate, then it looks like we'll need to wait a few days at least for the FC to go down before we can use the hot tub?


Mod Squad
LifeTime Supporter
TFP Expert
May 19, 2010
Tucson, AZ
I don't think you should not be adding all the Dichlor at the same time or as you noted, the FC will be too high.

Btw, your numbers are right. I would suggest half an oz each day.