water changes...

[marvinsae]

so i'm doing my first water change but i added cured live rock so there wasn't an ammonia spike, my nitrates are still pretty low. all i have in my 65 gallons so far is about 40lbs lr 2 damsels and 5 astrea snails. i have my salt water mixed in a bucket and i'm guessing i should wait about 24 hours to be safe? my question is do i have to siphon out the substrate aswell? my substrate is pretty fine so im worried it's gonna siphon some of it out. it's the caribsea brand. should i just leave the sand alone?