Crazy that you have to do that on a system this expensive. I've been back and forward with Red Sea customer service for months regarding this valve and Reefmat interaction.Yeah, the I programmed the hydros to turn off all flow, pumps, and the reef mat. I was mainly concerned that I would just brick the system so for now I top off by hand to make sure it doesn't go psycho.
This is what I got with the 1" Spear Gate Valve and plumbing component. Supposedly will convert the tank to imperial. Also I've read that you can use half a standard slip 1" union to screw directly in the Reefmat intake fitting. Should be a fun project.