Nope. Its mixed and dumped directly into the RO. If you are going to fully winterize your system you should start next season with fresh sediment and carbon filters anyway. If the DI is still new and good, you can take the cartridge out and store it in a ziploc bag.
As you know last winter was very mild. So if you store your cart in climate control. Run it once a week to keep the water and membrane fresh. Remember you can fill containers with pure water and add isopropyl and use a back back all winter long. Just save those wfp jobs for warm winter days. Jmo
The standing water in the system can bread bacteria that can negatively affect the RO. This stuff isn’t necessary but it can’t hurt to help prolong the life of the most expensive filter in your system.
So… what do you do if bacteria has already developed? I assume change filters. Should I soak the housings in bleach and rinse before installing new filters? (I bought a used unit and inherited this problem) thanks for your imput.
What type of system do you have? Do not bleach your filters!
You should just chuck your sediment and carbon filters, they are cheap. The RO membrane can be very expensive so before you chuck that you can take it out and soak it in DI water, this will help some. Your DI will most likely been to be changed any way so toss that and get some more ordered.
Once you take all the filters out, a small amount of bleach can be run through the housings to help kill anything growing, just be sure to rinse very well.