TDS meter

[Mightyfish]

I have used my RO DI unit for 8 months now and havent changed the filtration materials yet. My tank is 100 g and today i used digital TDS meter to test and it is still showing 0 ppm. I tested on tap water and it shows 100 ppm. Am i correct that i dont need to change filtration material yet?

 

[droth335]

Correct. 0 is the magic number and you don't need to change anything until that changes.

 

[rt67ghy]

If you haven't changed any of the filters in 8 months, I'd recommend you do. The carbon cartridges are supposed to be changed no more than 6 months apart. The carbon absorbs a lot of harmful chemicals and organics and it my have reached saturation point. If so it won't be able to absorb anything else. Also the white PP filters should be changed every 3 months or sooner. Some of the the dirt they have trapped may slowly migrate to your membrane so shortening its life and requiring an expensive membrane change.