Well this weekend I am trading in my 90 for a 125. I'm curious about peoples experience with moving all their inhabitants from one tank to another. How much water should I keep from the old tank? Is there going to be a huge spike from stirring up the live sand? I have about 60 gallons or so of ro/di water ready to go. I am also going to be adding some live sand from a friends tank to make up the difference to fill my new tank. Are there any more concerns I should have, or what else I should be doing? Thank you in advance.