I added a new Quiet One 4000 pump to my sump. I added a system of PVC and ball valves so that the flow can be directed to an external 30 gallon aquarium, phosban, charcoal and refugium.

Quiet One 400 aquarium pump.

I designed this system of PVC for flexibility and future expansion options. I added an extra ball valve so that I can route water to a charcoal filter if I want. I also added another ball valve that can either go back to the tank or to a future chiller.

Once the PVC comes through the wall it goes up the side of my new shelving system and into the external 30 gallon tank. The shelving system holds this tank, a kalkwasser drip reservoir and an auto top off reservoir. In the future I will add another refugium to the shelving system and a quarantine tank.

This external 30 gallon tank serves a couple purposes. First of all it adds water volume to the system which I think is always a good thing. With ball valves it can be isolated from the main system. The water is then pumped to a drain. 1/4" tuping is run from my RO water filter so this tank can be refilled. Once the new water is mixed with salt and other additives it is allowed to age for a day. The ball valves are then opened and this new water slowly mixes with the rest of the system.

Here is a link to some early stage setup pictures:
Early Building Pictures