Thanks all.
There will be 1 stand alone tank so I can isolate / qt if required, the rest will be on a 12 foot wall so I am thinking 3 x 4 foot trays and they will run a shared sump.
Lighting will be led (not radion) to keep the running costs down, possibly evergrow, still thinking about that.
The stand alone might possibly be 6 feet but like the twins divided at 3 feet with a swim through so I can run 1 side bb with high flow and the other with sand and lower flow.
This will be my one chance to do this and as much as I would love a big lagoon to give me more fish options I need to think practical!