The Switch From Crushed Coral To Live Sand?

I have a 125 gallon tank that has been set up for about 6 months with about 50 pounds of live rock, a bubble-tip anemone, 1 maroon clown, 1 false percula clown, a yellow tang, a snowflake eel, and two damsles. I also have a hammer coral, mushrooms, and some polyps.

Anyway, I want to switch from an undergravel filter and crushed coral to live sand, and I was wondering what the best way to do this would be. Obviously I'm still new to this and I don't quite know what to do, so thanks for your help!;D

 

thats a pretty good size job. if it were me. make 100 gallons of new saltwater in buckets. put the corals in the new water. drain as much from the tank without stirring anything up into separate buckets from the new water ( you only want clean clear water from the tank ). then put the rock in the new water or tank water. empty the tank and everything inside. clean the tank. put the rock back in the tank. then put the new sand in the tank. fill with water and put corals back in.

thats the short version, trying to keep it simple