OK so when i started my tank i got Crushed Coral substrate. I think its causing me algae probs. and i know its not well advised to change it all at once due to bacteria in the bed. How bad would it be to change it all at once. its a 29gal with around 30 lbs live rock. Bak Pak 2 skimmer. And in the instance i did how would i keep the new sand from becoming a slurry of that "gunk" i remember from when i started my tank. i have coral in it mostly LPS and some softies. HELP!!!!!!!!!