hi folks, i am planning using a dsb in my new 100g reef tank.sand over here in uk is expensive so i was intending using 2"-3" playsand with 2"-3" aragonite sand on top, seeded with live sand from a couple of sources.the playsand is brown in colour so doing it this way would not only save me money but would also give me more attractive white sand to view rather than the less attractive brown playsand.Can anyone see any problems with this idea????.Should i mix the aragonite sand using fine and sugar sized(if so what ratio?)or should i use fine throughout?