DI resin is not being consumed

[Nano30]

Hello, I've noticed that the last 2 times I've changed my DI resin cartridge using a BRS 4-stage filter RODI system, that it looks brand new. No discoloration like I'm used to. For example, I haven't replaced filter media in about 7 months, I see normal signs of use on the 2nd and 3rs stage when I replace it but not at all for DI resin and my RO membrane was replaced 7 months ago too.

Could there be a connection issue? I've refilled the DI myself in the past but the last couple of times I bought the prefilled cartridge which has a plastic cap at both the top and bottom of the cartridge. If I understand correctly, the water is supposed to flow up into the cartridge but it appears that the plastic cap at the bottom of the cartridge blocks any water flow and it seems like the DI resin is self contained not letting water in.

Do I remove the bottom cap? I would just do this and see what happens but I don't want all my DI resin to fall out the bottom if I am incorrect. I looked at videos and it looks like everyone leaves the bottom plastic cap on so I'm a bit confused. Any help would be appreciated.

Thanks

 

[exnisstech]

Are you getting 0 TDS?

 

[Nano30]

It shows 0 TDS in my cheap little pen meter (the built in meter worked for about 6 months) but in the past, the DI resin changes color significantly in 6 months.

 

[skiergd011013]

I have the same unit that i have been using for several years. Id guess 15 to 20 gallons a week. I have never changed any of its filters, and It still spits out 0 tds. The water that feeds it goes through a culligan sediment, and carbon filter first. So that probably helps preserve the rodi's filter media.