d.i cartridge

[kennethstowell]

o.k. i have a barracuda r/o unit, my question is, when do you change the d.i. cartridge? right now half the cartridge has turned color, should i wait for the whole cart, to turn ,or do phosphates start getting through as the cartridge turns color. any help would be great.

 

[AnotherGoldenTeapot]

If your filter has only one DI chanmber then it has both the cation and anion resins in the same chamber (this is common).

Only the cation resin changes color - the anion resins always stays much the same (usually brown).

What can happen is that the exhausted cation resin sinks below the anion resin - so even a fully exhausted cartridge could only show the used color halfway up the chamber (the top bit being brown).

If you can still see plenty of the oroginal colored cation resin (maybe it was green?) then you're probably okay.

If you're unlucky and both resins were different shades of brown to start off with then it's going to be hard to tell...

 

[Anonymous]

The only way to really know is with a TDS meter. Other than that, I'd say to change them before the color is completely changed.

Ty