Yeah, that's my issue with the Vanuatu rock. I originally had 75 lbs in a 38 gallon. It was literallly full. Now I have that 75 & another 15 in my 55, and it's full. Fortunately I have a sump with a LARGE refugium section on the 55, so I put the "extra" pieces down there. Still looks like a wall in my tank tho. That's ok, I kinda like walls, especially since it's got LOTS of interesting nooks & crannies due to the rock shapes.