I have a 90g and 80g connected by one sump. I want to change out all the rock and the new aquascape will be the negative space and the rock will all be dry. My question is, how can I make it so things don’t go all out of which when doing this? In my sump, I have some rocks, and in the 80g there are some rocks as well. I also have a marinepure rock in the sump. Any suggestion