Ro/di cartrdige question

[qstorm]

I have a 6 stage liquagen RO/DI system. I make 150gal at a time. It will take about 300 gal before the 1st DI cartridge goes brown. I normally replace that cartridge with the second DI one and put the new one at the end.

My question is, since the DI cartridge is depleted, should I be changing the 1st 3 has well.

Thanks

 

[xxkenny90xx]

Are you getting tds over 0? I know there are other factors but I don't change my filters until I start getting some tds readings

 

[qstorm]

Are you getting tds over 0? I know there are other factors but I don't change my filters until I start getting some tds readings

Sometimes I do, but its like 126-150