DI resin exhausting while system isn't running?

[Necrodaemus]

I just refilled my DI resin (mixed bed) and have installed all new filters and membrane about a month ago....new membrane was properly flushed with around 10 gallons before using and running through DI for product water.
I have a flush valve installed that bypasses the flow restrictor and I always flush the membrane backside for 3-5 mins before and after every use when filling my storgage container.
I noticed that after this last DI resin refill, it had barely exhausted any of the resin after filtering around 20 gallons of water....my output TDS from the membrane is around 3.
I just looked at the resin today when I went to top off the storage container and noticed that the resin had exhausted about 2 inches worth vs barely being able to see the color change at the very bottom of the resin the other day after using it.
This is indicating that the resin is being exhausted while the unit is sitting idle with no water running through it.
Is this normal? How can this be prevented to prolong the life of the resin?

 

[Tangdora]

Doesn’t sound normal. Are you running a drink water system as well. How long does the system run to produce 20 gallons.

 

[Necrodaemus]

Doesn’t sound normal. Are you running a drink water system as well. How long does the system run to produce 20 gallons.

No. It's a 50gpd 4 stage Aquatic Life RODI system that is connected to a spigot in my laundry room.

 

[Randy Holmes-Farley Verified Community Expert]

There is some salt creep across the RO membrane as it sits, and this can make its way slowly to the DI, but that is typically more of a long term increase in depletion rate, not a sudden loss.

 

[Necrodaemus]

There is some salt creep across the RO membrane as it sits, and this can make its way slowly to the DI, but that is typically more of a long term increase in depletion rate, not a sudden loss.

Yea, this happened over the course of about 4 days sitting idle.

 

[Shirak]

A flushing on the waste line bypassing the flow restriction won’t flush out the higher initial TDS RO water due to TDS creep when the unit sits idle. You need a bypass valve and line after the RO before the DI so you can collect the initial RO for a minute or two.

Pictures and more in depth discussion
https://www.reef2reef.com/threads/help-with-rodi-configuration.1137147/

 

[Necrodaemus]

A flushing on the waste line bypassing the flow restriction won’t flush out the higher initial TDS RO water due to TDS creep when the unit sits idle. You need a bypass valve and line after the RO before the DI so you can collect the initial RO for a minute or two.

Pictures and more in depth discussion
https://www.reef2reef.com/threads/help-with-rodi-configuration.1137147/

Exactly what I was thinking when I got to thinking more about it. I'm going to grab a 3 way valve to place between the membrane output and the DI with one of the lines running to the waste drain to hopefully solve this issue.