Jacob, I just finished with my rebuild the other day. I moved all of my rock over to my 100g tub (which you can borrow after I sell my rock) and moved my fish over at the same time. I used existing water and rock in the tub. In the tank I used all new rock and sand (Marco rocks has a GREAT deal on sugar fine, just wash it really well!) let it circulate for a few days over a month, and added my fish and anemones. I did lose a lot of fish, I turned down my powerhead (MP40) one night and I think the lack of flow kept the water from being aerated properly. My melanarus wrasse was alive, on it's side and breathing heavily. I cranked the powerhead back up, and everything was fine from that point forward. Just keep it well aerated, lit properly, and keep a heater on it. You'd be amazed at how low the temps can dip, even right now.