Tank liners and affixing rockscape

[Mariette]

Upgrading from a 55g FOWLR to 110g softies, LPS. Have never attached my rocks to each other. I like that I can move things around. I’m concerned about structures falling over or slumping w corals. So, I’m putting them straight on the glass and putting the sand overtop. Instead of sand 1st, then rocks. Figure this will prevent landslides due to digging. Concerned about scratching the bottom of the tank so considering a pvc sheet or something under the rocks. Anyone else do this or am I being paranoid?

 

[road_runner]

Upgrading from a 55g FOWLR to 110g softies, LPS. Have never attached my rocks to each other. I like that I can move things around. I’m concerned about structures falling over or slumping w corals. So, I’m putting them straight on the glass and putting the sand overtop. Instead of sand 1st, then rocks. Figure this will prevent landslides due to digging. Concerned about scratching the bottom of the tank so considering a pvc sheet or something under the rocks. Anyone else do this or am I being paranoid?

Putting rocks then sand is how its suppose to be. the other way will have the rocks unstable.
You doing it right.

 

[Mariette]

Putting rocks then sand is how its suppose to be. the other way will have the rocks unstable.
You doing it right.

That explains the lack of stability in my 55g lol. But aren’t you afraid of scratching the glass by putting rock directly on bare bottom?

 

[road_runner]

That explains the lack of stability in my 55g lol. But aren’t you afraid of scratching the glass by putting rock directly on bare bottom?

Nope.
Also scratch u donot see better than broken aquarium glass midnight lol

 

[Forsaken77]

I believe it's called a Phantom bottom. BRS has it in their videos somewhere when they setup the 3 cube tanks. I think it's a slab of polycarbonate, then siliconed.