Hooking up an RO or RO/DI system directly to your sump is a recipe for disaster. Avoid this costly mistake.
When it comes to reefkeeping, there are numerous basic tasks we'd like to automate. One of the most desired features is a way to top-off the tank automatically in order to replace water that has evaporated from the system, and many beginning hobbyists may not consider how important this is. As water evaporates, salinity rises in the display tank because salt does not evaporate. The water simply becomes more and more saline the longer the hobbyist waits to add freshwater.