158 > RO Membrane > 1 is really good puts you at a 99% rejection rate. Which means that your DI resin would be bad. I personally have never had good luck with color changing DI resin. For a bit I was burning through a DI canister every month which is what lead me to dig in and figure out how to optimize my system.
If you ever get around to testing your waste/production - to achieve the best functionality, from the specs I have read you should divide the production amount in 60 seconds by the waste amount in 60 seconds. Production_RO/Waste_RO = %... This should be 1/6 on the low end and 1/3 on the high end. Anywhere in between lets you know that you are in an optimal range for your membrane's efficiency. Outside those ranges will determine if you need a different flow restrictor. You will experience fluctuations in those numbers with a change in water temperature and water pressure.
Last thing that may be of some help. Not sure how you run your RO unit but if it is plumbed straight into your tank then when the unit auto shuts off the 158TDS builds up at the membrane, when the unit is turned on your DI is scrubbing that 158 all the way down to 1. One way to lengthen the life of your DI is to have a waste valve after the membrane that you run for a few minutes to dump high TDS water out and then turn it off so that you have a lower TDS going into the DI. This is how my system is setup and it allowed me to get an additional 2-3 months out of my DI (Which I have to replace every 6 months due to depletion).
Good luck.
If you ever get around to testing your waste/production - to achieve the best functionality, from the specs I have read you should divide the production amount in 60 seconds by the waste amount in 60 seconds. Production_RO/Waste_RO = %... This should be 1/6 on the low end and 1/3 on the high end. Anywhere in between lets you know that you are in an optimal range for your membrane's efficiency. Outside those ranges will determine if you need a different flow restrictor. You will experience fluctuations in those numbers with a change in water temperature and water pressure.
Last thing that may be of some help. Not sure how you run your RO unit but if it is plumbed straight into your tank then when the unit auto shuts off the 158TDS builds up at the membrane, when the unit is turned on your DI is scrubbing that 158 all the way down to 1. One way to lengthen the life of your DI is to have a waste valve after the membrane that you run for a few minutes to dump high TDS water out and then turn it off so that you have a lower TDS going into the DI. This is how my system is setup and it allowed me to get an additional 2-3 months out of my DI (Which I have to replace every 6 months due to depletion).
Good luck.
