What to stock

The 230 gallon display is not set up yet. I am currently cooking about 400-500 lbs of rock in the garage and it will be around another 4 weeks till its done..

I have a 50 gallon set up now as a qt.

Can I add all the clean up crew once I have the main tank going? Is it ok to just drop in 200-300 crabs and snails all at once? or do I want to qt them first?

And if I need to qt my fish and corals for three weeks should I add them to the qt soon? So they will be ready for the display tank?