Need inspiration... "the gem cave"

[Heatheranne]

You could clear silicone the gems to glass and then run the lights behind it. Any GS foam with colored drylok could then be filled in around the gems.

[deranged chipmunk]

depending on how big the gem wall will be, you could silicone multiple lights to the tank wall and silicone the gems over and around the lights. different colors of light will create different effects. example, a blue one high, a red one middle and another blue low "should" give you layers of blue/purple/red/purple/blue-ish gems. that is, if you are using clear quartz and assuming a roughly 160 degrees of spread from the light strips. it's tough to see what vision you have in your noggin, but that's how i see it in my deranged mind