Need technique for creating Coral runway.

Go to any store that sells aquarium products and you can get the real thing. Crushed coral is commonly used in aquariums for modifying the water chemistry.

how about fine kitty litter? couldn't that be used?

Thanx tho9900, there is always someone here willing to help.

this is in 1/48 or 1/72?

if it is 1/48 you could try using model railroad ballast, they have it in varying colors (hobby lobby or a hobby store) but from memory it would be about the right size. They have different grades of it too so there is a bit to pick from...