TDS Meter Readings

[Blue Ram]

I was thinking it is probably time to replace the filters in my RO/DI system. I tested the water from several sources and here are the readings:
- DI (used for reef system) 011 ppm
- RO (used for drinking water) 022 ppm
- freshwater invert tank - 199 ppm
- discus tank - 202 ppm

I have not tested the RO membrane as the system has been used for only 11 months and the product info indicates replacement every 2yrs.

Is 011 ppm acceptable.