kent maxxima?
 

so im looking to buy replacement cartridges for me rodi unit. but i can remember if i purchased the maxxima 35 or 60 gpd model. does anyone know how to tell the difference? im replacing them now because the reading is 2 tds right out of the hose. should i replace all of the cartridges or just ro and di?

I can't remember if the membrane states it or not but a rough way is to see how many gallons it produces in an hour and then multiply by 24 if its over 35 it's probably the 60gpd model. I'm not positive but you may even be able to use either filter in the unit. As for the other filters the Kent replacement schedule is 6 months for the particulate and charcoal filters and for the DI change when the color change is 1" from the top of the canister. RO filter is 3-5 years.