Very interesting project. I like the home design except for the distance between the parking area and the kitchen. I am sure you mulled this over, but that will add a lot of traffic to your study.
The round tank is interesting and I am very curious how much distortion there will be with the round 1.5" material. I know it gets less with size so it really may be no issue at all.
Many have commented already but I would seriously reconsider your QT/Hospital tank situation. These should NEVER be connected to your main in any manner, whether you feel "safe" with the valving and bypasses. You mentioned using them more for acclimation and I would encourage you to use a design more like mine.
I have an isolated QT tank with its own filtration, skimmer, lighting, etc. and most importantly (IMO) automated top-off. This is a multi-use tank for all inbound corals and fish, as well as a grow-out tank for snails. I have another spare tank should I need to get aggressive with meds, but as a rule, I don't do this anyway.
Now for the acclimation part of the process, I have a line going from my elevated refugium to a gate valve, and then a float valve mounted on the QT tank. After about a month of QT, observation, feeding etc. I will slowly fill the QT with system water by opening the gate valve, and drawing off about a gallon of the QT water per day. It re-fills with system water and I usually do this process for about a week.
This provides excellent acclimation while allowing the fish to be in a relaxing environment. That way, when they go into the main, all they have to worry about is being eaten! :lol: I also use a T-5 array that allows for different types of lights to be on or off. So I can adjust lighting based on what is in the QT.
I will PM you about another issue that I don't want to get flamed over. Good work so far, and keep refining the design. :thumbsup: