Flaxon-Waxon
Aquarium Advice Addict
This isn't quite true for every load (motor, etc), but for this situation, it should be close: amps = watts/volts.
So, in this case, IF (note the big IF) we have 120 volts at the fixture plug, and the true wattage is 216, the amps should be just shy of 2. The usual problem is that the true numbers, as measued on the circuit, are different than what the label says we should find. A little corrosion and a loose connection somewhere and a ½ amp load is suddenly 3 amps - and every load creates heat - which is often not dissipated adequately.
Cool, thanks... So a 15 amp timer SHOULD suffice, eh?