Letting the water degass overnight should clear the chlorine prior to adding to the tank, especially if you have a pump running on it. Or you could pick up an R/O unit or tap water filter.
I would also try the vinegar and water trick, just to rule that out. We have a 1.5 year old MCE600 that works perfect even with Prime added to the water, but we also have a client's skimmer that is doing this exact thing and we just cant figure it out.