While bubble tip anemones can be kept with other types of anemones, I'd be cautious about putting more than one type of anemone in such a small tank. Most anemones, especially host anemones, will need more space than what a 24 gallon tank will provide, especially if you're planning on more than one type of anemone. In your size tank, I'd stick with one type of anemone; you'll most likely have the best results with caring for them.
As for sand, I know others have used fine sand from Home Depot or Lowe's in their tanks without issue, but I'd be careful with that, as I have known others to use sand from a hardware store, and have had their tank crash because of it. You can always order fine grained sand that is aquarium safe through your LFS or online.