question about the carbon cartridge bought few month ago

[Explorer]

Just wondering if anyone know what the color rings shows up on the carbon cartrige for ro/di system means. Time to change? someone told me change every 9 to 12 month, is that correct? or do I go buy the monitor, as long as light turns green when I press it, don't change.

The cartrige were bought about 3-4 month old. I have two carbon cartridge in my ro/di system, 2nd one is placed after the one I am talking about(looks like new still).

it is about same distance between each ring....kind brownish in color about 1/2 cm wide.

thanks in advance.

 

[argi]

To my knowledge the only cartridge that would change color on an RO/DI system is a color change DI cartridge. The carbon blocks do not change color. I change mine about every 6 months (sediment, carbon and DI) depending on my usage. A monitor is probably the best route to go though, so you are not guessing.

HTH,

Keith

 

[Explorer]

I see...thanks....one of my friend brought up a interesting point...he says maybe that's how the water flow into the cartridge, so the sediments that didn't caught by the sediment cartridge caught by the fabric on the carbon cartridge. Well just on the safe side. I am going to change it tonight.