Advice? DI resin

I have a 5 stage brs ro di plus I bought second hand a while back. I'm just wondering how long your guys' di resin lasts roughly? I use the brs color changing stuff and I'm only getting about 60 gallons until it exhausts completely, is that normal? It runs at about 52 psi and I changed the sediment and carbon blocks before the last batch with similar results. Maybe the ro membrane is out? Thanks for your input

 

I'm not sure how old the membrane is because it's been in there since I bought it. I've been thinking about getting a booster pump but i wanted to see what you guys thought first. The unit came with the input and output tds meter. Maybe I should just stop being a cheap *** broke *** college kid and start buying new equipment hahahah thank you guys

 

Yeah the meter seems to respond quickly to the changes I made so it seems to work good, oh and the tds meter is hooked up to the input and the output of the di canister. so here's what I found: if I hooked it to the ro membrane connected to the sediment and carbon blocks it would come out at 5-6 tds, if I hooked it up to solely the ro membrane it would come out at 9-10tds(this is before it get to the di resin). Then the output of the di resin would be 1-2 tds and 3-4 tds respectively and this is completely orange or yellow or whatever exhausted color is remember.

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No sorry I didn't measure what it is for just the pre-filter blocks, the 5-6 tds was through the pre-filter blocks and the ro membrane but before the di (which would be the regular measurement I was reading before but I moved it so it would read the water before it got to the Y of the waste water) . The raw water coming out of the well was at 327 tds and when ran only through the ro membrane and nothing else was at 16 tds.

 

What psi is yours running at?