Kirk from Atlanta, GA here. First, let me say that in searching these forums it seems like a very valuable resource for both the beginner and experienced marine enthusiast, for that thank you to the admins, moderators, and users on this board.\n \nBefore I start asking questions that I've been unable to find the answers to with some searches, I want to make sure I'm at the right place. Is this forum dedicated to those with reef aquariums only? I am just starting, and my thinking is that I should start with live rock before I go with a reef setup. In short, do I belong here, or perhaps I should be on different forums that are less advanced?\n \nThanks!\nKirk\n \n \n*edit*\nLet me give my basic setup for the marine aquarium:\n \n75 Gallon non-drilled tank. Two large powerheads, about 20 - 25 lbs of live rock (doesn't look like much in the aquarium at all) with about a 5 gallon bucket and a half of live sand. The rock and sand have sat almost dry for about a month after being used before, so the rock and sand may no longer be "live". I have a sump setup with about 8 lbs of live (maybe dead) rock in it, a protein skimmer, and when the water is filled to the "water level" line in the sump, I guess it's about 3 or 4 gallons of water in there. I also have a 9 watt UV sterilizer. I replaced all the tubing with black vinyl, and set everything up about a week ago. Tested the water, apparently it is still cycling as the nitrites are kind of high.\n \nMy main two questions to start were:\n \nHow much live rock would be advisable for this setup? What I have in there does not seem like much at all, not even enough to go across the tank (4 feet) sitting side-by-side.\n \nI've noticed I have considerable evaporation. Should I be replacing the water with regular (non salted) RO water, or should there be salt in it? I know salt doesn't really evaporate - but I'm not really sure how to read the little salinity/specific gravity thingy to know what I should do.\n \nThanks, guys.