so i have my tank set up for about 3 and a half months. i was just going to a LFS and they led me in the totally wrong direction. i was told i didn't need a overflow. when topping the tank of i could just use tap water directly in the and just squirt start right in not to measure or anything. in my tank i have THREE DIFFERENT SPECIES OF TANGS. i was later told by another that was a dangerous situation. oh and what the other fish store was amazed by was that i was told to only do a water change if there is a problem other than that not to worry about it. so if you don't mind please steer me in the right direction. :sad