My black Percula clowns spawn regularly but because they are in my reef tank with other fish the young don't survive. I tried moving them to another tank but they stopped spawning.So I put them back in their home and they went right back to it.My tank is 150 gallon with live sand and plenum and has been set up about four years.I have several anemones in the tank as a refuge for the young but so far no luck. Also the Australian government has banned imports of coral sand calling it an invertebrant even when it's dead.Is there a substitute?