Ro/di R.i.p.

[bourbeaue]

I haev been running an OPTIMA Vision series RO/DI filter for about 6 months. A few weeks ago I checked my TDS meter which indicated a higher ppm on the output than on the input. I proceeded to change the carbon cartridge and the floss cartride as well as the DI cartridge. It was fine for a few days, then it started climbing high again (200ppm). I disconnected the DI stage and the value fell to 70ppm. Now, even after flushing the membrane, I can not get the output below 99ppm 9inout is about 130ppm. Not much of a filter... Does this sound like I should change the RO membrane ? It should be good for two years according to the manufacturer but it has not been that long...

thanks for your advice.

E