View Full Version : Compact 75g and high TDS

speckled trout
04/25/2008, 11:25 AM
I recently replaced all pre-filters, DI resin, and RO membranes on a 75 Compact RO/DI unit. I didn't purchase the unit and have none of the directions for it.

I did not realize that you needed to "flush" the carbon, DI, and RO membranes before using it. I only found out about this after the fact.

Well, after installing the new ones I initially got a TDS reading of 0ppm. This continued for about 40g. After that my TDS readings began to creep upwards until now. They've reached 15ppm.

I've been told that I probably ruined all of the new canisters, DI resin and RO membranes because I didn't flush them first. Is this true and what can I do? I just spent around $80 replacing them and didn't even get enough water to do one water change in my tanks...ouch!

I realize that ignorance isn't an excuse, but this is terrible.

Help, please. I would really like to filter my own water, but I'm close to giving up.


speckled trout
04/28/2008, 07:29 AM
Is anyone out there? :confused:

04/29/2008, 05:39 PM
i think your fine maybe its just a bad DI cuz I just bought all new filters and it said just to run it for 3 gals and it should be fine so I hope... Just flush them now and see what happens.

05/22/2008, 01:31 PM

The unit is fine, but the DI sounds like it's been exhausted. You just need to replace the DI.

Air, Water & Ice staff