Update!
Got one of my darts plumbed. It will feed the skimmer, ref, seahorse tank, and UV.
I also got my water change/mixing system hooked up. No more Buckets!
Looks confusing.
The top tank is the measuring tank so i know how much water to take out of the tank. The bottom tank mixes the saltwater. I can pump water from the sump to the top tank or to the drain. I can drain the top tank and the bottom tank to the drain (a hose actually so i can fill buckets or whatever) I can also pump the salt water back into the sump. All from one pump.