Adding Large Boulders To Tank On Open Base Stand

[N0body Of The Goat]

I've got a 48x12x15 tank that came with a stand which is supporting the tank around its perimeter, along with three front-to-back support struts in the central third. The glass is 7mm thick.

Would I be seriously risking a structural failure by placing one or even two boulders, each with an approximate footprint of 8"x6" and a weight of 7-9Kg, in an end section of the tank?
How about in the central section which has the three struts underneath the tank floor?
Or should I only think about adding either of these two boulders to one of my other tanks that have complete floor support?

I expect this whole thread may cause a giggle or two to those of you with Rift Valley hardscape experience, but I'd hate for my idea of a part bogwood / part boulder look to end in disaster!

 

[holidayinn]

if a big concern you could use eggcrate to displace the weight, something like...

http/www.ebay.co.uk/itm/Filter-Media-Grid-Egg-Crate-Koi-Fish-Pond-Marine-Coral-/280463489831

 

[GrayScale]

Or possibly cut a sheet of 1/4" plywood to sit on top of the stand under the tank.

 

[N0body Of The Goat]

Thanks for the suggestions. As it happened, I had underestimated how much of the tank floor would be taken up with the intended bogwood (to create lots of natural hidey holes for young Synodontis and soften the water a smidgen), so there was nowhere near enough room for either of the boulders after all! Might try and add them to the garage 5x2x2, which has its base fully supported by the stand.