Get a lid ASAP!!! Frogs jump and are excellent escape artists when they're determined. Metal screen lid and cover it 3/4 Of the way with plexiglass with air holes drilled in it or with plastic wrap. D has told you what options you have for heating. Be sure to buy a lamp that has a dimmer switch and is for incandescent bulbs. Make sure the bulbs wattage is no higher than 50 watts.