Thanks for your help everybody!
I used the idea of skimming the grass and i got a few bugs for him...I'm not sure if he ate them or not. There is a big rock for him to climb on but I think I need to make more land surface. A second one will probably be a frog in a day or two.
I've been raising them as a science project for my preschoolers but my husband is hoping to keep them as pets after. We have a very large aquarium that should house them fine. I\ll worry more about that as they get bigger though.

I appreciate everyone's help!