I think you should definately be getting some better results. I know that after mine goes through the RO it is down to about 40 or so and then 0 after the DI. I'm sorry I'm not much help in fixing your situatution. Hopefully someone else here has some ideas.
Have you contacted the seller? Maybe he has some suggestions. Good luck.
Something must not be hooked up right. You should be in the single digits to 0 with a new unit. Run it a while and see if it gets better after it breaks in.