Shock recommendation

Welcome! We do not recommend shocking. Instead we recommend you read the following and use liquid chlorine or a SWG.

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Update- looks like you’re not new! Stick with the liquid chlorine you’ve been using as noted in your pool math logs.

Menard's has about the best price on liquid chlorine available in the Chicago area. $4.44 per gallon after discount. Link to Menards--> Pro-Clor Liquid Pool Shock - 1 Gallon

To clarify for @Laziebun

The term SHOCK is used in multiple ways.

Shock can mean to raise FC once a week to a high level.
Shock (as you can see on the Menards bottle) is nothing other than liquid chlorine.
Shock can also mean a powdered form of chlorine, like cal-hypo or dichlor.

TFP does not recommend doing the first definition of Shock above. As Jim says, follow the FC/CYA chart and maintain the appropriate level of FC for your CYA...there is no need to Shock.

If you were asking about finding the second definition of shock (as on the Menards bottle), Menards is your best bet in the Chicago area.

If you were asking about finding the powdered form, we recommend using them sparingly, as cal-hypo adds calcium to the pool water, and dichlor adds CYA. Both of these chemicals (calcium and CYA), can only be removed from the water by draining and replacing water, so use them sparingly.