We have this play construction sand that we use. I haven't had an issue with it so far. Although at Lowes I have noticed that the content varies. One time it will be almost strictly fine sand and the next it will have quite a bit of rocks in it. But I do like it, make sure you invest in a reptile poo scooper, rather then a cat one and also a spade comes in handy since the sand is to water absorbent. Make you change it out after a couple weeks, I usually change it out at least every two weeks, although it is usually every week.