Clam experts need help

[Warnberg]

I have a blue maxima that I can not get to attach to a piece of rock so it stays on the sand bed and in my opinion to far from the lights. I would like to get it to attach to a piece of rock about half way up the tank but it always hops off.
What I am trying to do is get the clam to attach itself and then slowly move it up in the tank to get it closer to the lights.

Is there some trick to getting this clam to attach?

Thanks

 

[Electrobes]

Patience... these guys basically need to be positioned in a spot where they can not get out so easily, where in enough time they will form the threads and attach to the rock.. just keep watching it and place it back in the rocks if it jumps out. Often times my snails keep knocking it off.