Get dead live rock and attach it to PVC to make pillars, tunnels, and large caves, and you will not have to worry about the live rock formations collapsing on the fishes. The only problem with dead live rock is that you'll have to introduce the BB to the aquarium in order to colonize the rock during cycling.
Another option would be making your own live rock and molding it to the back of the aquarium to avoid taking up floor space.
Another option would be making your own live rock and molding it to the back of the aquarium to avoid taking up floor space.
