If you smell "chlorine", then you have goo in the pool that needs to be burned off.What you're actually smelling is the chloramines, which form when chlorine engages the goo to try to kill it--and that's what it's in there for. However, if all the chlorine you're producing overnight is used up fighting "goo" that's already in the water, my concern is that it will leave little left to fight goo during the day as it's introduced by swimmers. I think you probably still need to shock the pool to eliminate ALL the "goo" so that your SWCG can then do a better job of maintaining chlorine levels.

Just curious, have you checked your chlorine levels in the mid-morning? I'm just wondering how much chlorine is in reserve for the day after the SWCG is turned off?

Janet