umm.. before you put the sand..
1.) rinse the sand until the water clear in a bucket or something.. not in the tank!
2.) turn off your filter so the filter doesnt suck in the sand
3.) turn on your filter to help clear the water up but before you turn it on, make sure the sand or debreez settles
then turn it on..
4.) even though you wash the sand, something the water will stay a little cloudy, but that should be fine
it will take like 1-2 day to clear up.. sometime faster..i also think it depends on what sand you buy. but
i used around 10-15 lbs of sand and it filled up like 1 inch from bottom up or so in my 55.. but now it all mess up cause my cichlids dig and made mountains..
hope this helps =0)