A quarantine alone probably won't do the trick long term as many algae can lie dormant for a long time. I would say quarantine fish in a clean tank, completely bleached after every batch that makes it through, for 2-4 weeks. For corals I really only see taking fresh frags as a possibility. Any substrate will eventually bring in just enough algae cells that when the water quality has a hiccup will grow and then what's the point. Fresh cut sps and 'center cut' lps would be safest. Zoas would be difficult.
In research to keep large systems (usually fw zebrafish) clean of parasites they start out sterile and raise every fish(hundreds to hundreds of thousands) in there from egg, and they rinse them in bleach before they hatch just incase. Even these systems with 10% water changed daily with ro and lab salts aced back grow hair algae, not all but most. They don't have any type of parasite tho.
Your not really gaining much as so many algae have the ability to transfer via airborne or longterm dormant cysts. In the end if water quality allows for algae to grow some kind will find a way. Usually it's the slimy kinds that are more unicellular and tend to dissolve when you try to remove them rather than a solid mass you can remove.
But hey it's worth a try and I would do it if I had a new tank and wanted to experiment a bit, I just wouldn't do it as my only tank. Something to remember separate cleaning equipment is better than trying to sterilize between tanks, eventually you'll forget.