Floating reef support on thick acylic

[Dbasileccim]

Hi all. I'm in process of setting up an oceanic 144 gallon 1/2 cylinder with depth of 30 inches and about 60 inches wide. I'm thinking about setting up a couple of floating islands or a long shelf across the entire bottom with floating islands on them.

I have found some extremely heavy duty acrylic that is about 1.5 inches thick x 5 inches wide by 36 inches long. My plan is to put a long horizontal plank of acrylic with vertical acrylic supports of the same material holding it off the bottom. I'll hide the acrylic by gluing rock rubble to any exposed edges and rocks on the bottom hiding the supports at the bottom.
My concerns are that since I will be able to put a significant rock structure without bending this very thick acrylic what kind of risk will I have of breaking glass where the supports contact the bottom? The supports will be 1.5 inches thick by 5 inches wide at the glass. The glass is 1/2 inch glass.

Do You think I need to put a horizontal plate of this thick acrylic under the supports to spread out the forces flowing through the supports to the glass?

Any ideas are appreciated.

thanks.

 

[jeffrey750750]

I myself would for peace of mind

 

[tamanning]

The piece on the bottom does not need to be as thick but should still be fairly substantial.