okay, so what is the math I have to do to figure this out and do it right the first time around?
Keep in mind that I will hopefully be moving in about two years, and when I do, I will be selling this set-up (keeping all my rocks, etc) and getting a fantastic BIG tank (?90 gal? 120?) so I do not feel the need to go all out on this - just to make it work really well for two years...
Okay, what you could do is make them all consecutive:
Tank flows into the fuge.
Fuge flows into the wet dry
Mag 5 pumps from the wet dry to the tank.
Throw the rio away or use it for making up salt water.
Option 2.
Tank flows into wet dry.
Pump pumps water into the fuge. Use the one that you use to make saltwater. Use that RIO to make saltwater.
Water flows back into the wet dry.
mag 5 pumps water back into the tank.