Paperwhites will thrive in any planting medium. I grow mine in a 4"-deep china bowl filled with pebbles and water. The only downside to the pebbles is that it prevents the staking of the flowering stalks.
Paperwhites can quickly attain 18" or more in height, and then collapse in a miserable heap just as the flowers open. The cure for such exuberance? A bottle of gin.
After the bulbs have grown in a sunny window for one week, pour the water off, and replace it with this solution: one part gin to five parts water. If you don’t have gin, use any spirit which is 40-proof, such as rum or tequila. As evaporation occurs, top off with the same cocktail. So inebriated, the plants grow to only half their normal size, but with flowers just as large and fragrant as usual.