Yes, in a 2o gal. the basking light will take care of heat. I have used many ZooMed bulbs, and they last months not weeks. It depends on the bulb though. The most important thing to look for in a bulb is UVB. Don't buy things that say "full spectrum" assuming that means it has UVB. Make sure the box says UVB. Don't assume! MOST reptile bulbs do not have UVB, they only have UVA.