DI/RO System Issues

[reefcrazed]

I've had a 4 stage RO/DI unit for a number of years. Seems like lately when I refill the DI and change a couple other filters my dissolved solids only stay on 0 ppm for a few days. Any suggestions to extend my purity, such as add another stage or a pressure pump?

 

[reefkid007]

When last was the membrane changed?

 

[bcavalli]

Assuming all the filters are new or don't need to be replaced. I would maybe add a second DI filter. It will save you money in the long run anyhow and will allow you to completely deplete the first canister DI resin before needing to replace it. If you do add the second DI filter go ahead and add a y connector and valve before the DI canister to flush your system and cut back on DI resin waste. One other option is to also add a flush kit to your membrane if you don't have one already. Just a couple of thoughts.

 

[jennm]

How old is the membrane? And do you flush the membrane periodically?

What's your inbound TDS?

Jenn