of course you need heatJust solving one problem at a time
55gal is big, and may not really be cheap to heat. The best heating methods are usually the priciest. You will need a good Thermostat to regulate the heat. Spyder Robotics has some great T-stats, and you can buy some cheaper ones at Reptile Basics. Reptile Basics also has Flexwatt - for a 55gal tank, I would suggest a pre-wired 1ft of 11" flexwatt. Or, check out the radiant heat panels and ultratherm heat pads...I've never used those two, so I don't know how affective they are.