Auto Chlorinator

[krcossin]

I have an auto chlorinator we use primarily for when on vacation, throw in several tri-chlor pucks and forget about it. We come back and all is well. However I last filled it a few weeks ago and as I am watching the chlorine level with my test strips, it's still at normal level (around 5ppm). So with the pump off, I spin open the top and there are still a few half disolved pucks with very low water level (oh and it smells strong!) So with the cover off, it refills and then I twist back on the top.
Is it normal that the water level gets so low, and it works for so long? btw, I have the dial set to 4.
I have the middle one:

 

[MarkC]

If the chlorinator is the in line style they work by using a 90degree elbow into the water flow to scoop up some of the water in the pipe going through and divert this to the small tube that erodes over the pucks. When you take off the cover you release the back pressure normally present and the water can fill up faster. If you had a clear lid you could probably see this but thios has been my observation with these devices. The last of the pucks take a while to dissolve since there is very little surface area exposed to water. For more consistant flow add a puck or 2 every couple of days as long as your CYA is OK.

 

[krcossin]

Or maybe I should just put a rubber gloved hand and pull them out.
Thanks for the info.