I'm not sure. A lady from BYC had a blog and said she has used construction sand for a few years with great results. I got mine at Lowes for under $5 for a 50lb bag. Other people have been saying to use play sand. I guess everyone has a different opinion. I'm going to see how the construction sand works. I have to get a small colander or scoop tho. They say colander is better until poo gets bigger.
