Zapman

Our heater will get incredible corrosion in a very short time, causing it to short to ground. This last time was less than 5 months. Our circ pump runs 24/7 and we never use the big jets. We use chlorine but must be missing other chemicals that is causing the corrosion? We have used our tub every day for over 15 years, a morning routine. Current tub is 5/6 years old. Or could this be cheap heaters? I finally ordered a special(green) coated heater element hoping that will help. Any help is much appreciated.