Sorry in advance for the long post... Well I've ordered the tank and went the custom route from Planet Aquariums. Tank dimensions are 84.5"l x 24.5"w x 20"h. Tank will be 179 gallons. Huge thank you to Wayne at Live Rock Aquatics! I went with a center internal overflow. Debated the external overflow but decided against it since the tank will sit against the wall. It would be too difficult to reach with the length of the tank. I wanted a longer tank but wanted to keep weight down since I'm on a crawl. I plan to reinforce the joists with 2 jack posts supporting two 8ft long 2x10s sandwiched together. Feel free to chime in if you don't think this is enough. I want this to be overkill. I plan on building a custom stand out of 2x8s spanning the top and 2x4s supporting it and skinned with 3/4 inch oak plywood. I'm using rocketengineer's design off reef central. I actually had him review it. Thankful to find an expert for this! Under the tank, I will have a bashsea smart series 30x15 acrylic sump. I really liked the layout of this sump. The top has even been routed to manage cords from equipment and has places to hold probes if i ever add a controller. It will house my Skimz algae reactor in the first chamber and a Red Sea RSK 600 protein skimmer in the 2nd chamber. The tank will be heated by a BRS titanium heater with an inkbird controller for safety. My return pump is a Maxspect Jump DC 12k. I'm still thinking about ATO options but leaning towards the Tunze 3155. I also have a dosing pump if I ever start growing sps like Aaron. In the tank, flow will be provided by two Icecap gyres. I liked the idea of two pumps on one controller. Tank will also have returns on the back wall on each end. Tank will be lit by AI Hydra HDs. I will make certain to add lots of pics of each part of the build process. Also I might need some help getting this thing in the house. I don't think I should do what Aaron did. I'm really looking forward to getting some tangs and other fish not suited for life in my 75.