In case you are in a rush for this info I will answer this one for you.Sorry I'm kinda confused, acclimate them to the substrate or to the water?
Burbon means the water, some substrates can alter the water chemistry, coral gravel\sand being a prime example. Try and use a substrate that is inert (doesn't alter the make up of the water). Most aquarium sands and gravels are generally fine....just ask before purchasing.