I think my SWG (Aquarite) cell may be going out. It is 6 years old, so maybe its time is up. I'm having trouble maintaining chlorine levels in the pool. The cell has been recently cleaned, and I recently did a full algae kill, so I don't think that is the issue. I tested the water coming out of the return lines, and am only getting about 2.5 ppm Cl, which seems really low (the pool is currently at 0.5 ppm, before I added bleach). I have not measured it before, so I am not sure what it should be, and I can't find any published specs. The SWG is set at 90%.
Does anyone know what level of Chlorine should be in the return water?