Just starting a reef tank; Have a RO/DI question

[Aquattro]

Originally Posted by newreefer_59

Is it generally recommended that all water be run through a RO/DI unit prior to adding salt in my reserve tank?

Some people just use tap water, but yes, it's generally recommended to use RO for any reef application.

[Jaws]

Even living in a city that apparently has a lower TDS reading than most in its water supply, I still noticed a substantial difference to overall system health when I switched from tap water to RO. Don't be fooled by store bought water either. It's not much different than tap water.