Packing DI Resin Container Correctly

[redfishbluefish]

I regenerate my DI resin....been doing it for years. I actually tried setting up a dual single bed unit to simplify regeneration by keeping the cationic and anionic resins separate by repurposing an old RO unit.

Extremely perplexing, I could never get this to run right and finally gave up. Here's the TDS before and after the dual setup:

So I ended up going back to mix bed resin by actually mixing the anionic and cationic resins. Water now came out at 0 (zero) TDS. Life went on and I enjoyed reading posts about RO/DI units, with one member always touting the superiority of Spectapure resin. So out of curiosity (and the fact I need to regenerate a ton of resin), I looked up a Spectrapure mixed bed cartridge and was surprised to see two different layers within the cartridge.

It would appear that Spectrapure packs the two resins independently. I have always literally mixed the two resins together for my mixed bed. Have I been doing it wrong?

 

[AZDesertRat]

You have been doing it like everyone else but Spectrapure does this to take advantage of pH changes within the resin bed itself. Certain resins work better at certain pH levels.
They have a long term test facility where they test every possible brand, resin batch and blend imaginable and learned this long ago. They are not content to be just average.
You will find you can never ever regenerate resin back to 100% at home and it continues to lose its strength from then on until it is no longer feasable to regenerate it anymore. I find its not worth the trouble or having the chemicals around the house when I can get over a year out of a single DI cartridge from them. In the past I was going through a new cartridge or fresh refill every 150 gallons maximum, there really is a difference.
What Spectrapure doesn't tell everyone is they are big in the groud floor of the hydrogen fuel cell business where ultrapure water is a must, reef RO/DI is only part of what they do. Their research really pays off.