what type of sand to use?

goldenear,let's try to keep religion out of the conversation and stick with tried and true facts,like my Alien Sand.Only 2 pounds left,get some while you still can.

Silica sand it what you are looking for.

Should be fairly easy to find, as it's used for sand blasting (bone dry if stored properly and inexpensive).

Wear a breathing mask/cloth when pouring it as the dust is not something you want to inhail.

Perform the task outdoors.

Research silica sand for your application in order to judge the previous sandbox responses to your query.

I used washed sand in my speaker stands.