How much TDS is TOO much?

[sm1983]

I know, I know, 0ppm is the only good TDS reading. I am running a might mite and currently getting 8ppm. I have been using 4ppm water for a couple of months. Do any of you run with anything other then 0ppm? If so how high is too high in your opinions?

[roscozman]

I have heard 4ppm is about the highest you want to accept. Try doing a system flush and see if that helps.

[ReefCube]

i say it depends on what corals you are keeping

[JimD]

I never let it go above 3ppm, when it reaches that, I change all filters including DI but not the RO as long as the RO effluent is around 12ppm or so...

[mikedelgado]

Anything above 0 tds after the di tests positive for nitrate for me. Once the di is exhausted it starts to release what it had previously captured, you could actually end up with higher tds after a spent di then what is coming out of the ro. If you are not going to refresh the resin then I would suggest taking the di part off line till you can get some more di resin

[sm1983]

I have the might mite unit but I really dont understand what all I can do to maintain this thing. I am currently testing at 8ppm. So if I understand this right I should test the TDS after the RO and if that is under 12ppm I should just change everything after the RO?

What exactly does a "system flush" entail?

Thanks for the help!