just looking at the video and the coral growth suggests everything from sun light to tidal flow is replicated in that tank. i built a 3000 gallon aquarium years ago, it was freshwater but I managed to replicate tidal flow in it much the same way as the video but the video represents a tank in the 10s of thousands of gallons. Just the tidal flow would be very energy consuming... It's more or less circular shape would make it a little easier to do tidal flow but the lighting represents a significant energy debt as well. The water filtration probably takes place in a remote location. I would love to see the filter, i wonder if it's biological or chemical or natural. I like natural as much as possible but it takes up a tremendous amount of space.
If the SPS corals are real, and they do appear to be real, then the planning behind this tank is ingenious... It would have to be set up for several years and be in near perfect balance for those several years..
Octopus used to be my main focus, they are not hard to keep with the proper equipment but they do represent a significantly higher bio load than a fish of similar mass...