yes watts do equal lumens but different lights have different wattage to lumen output ratios an hps will put out more lumens per watt than a cfl will, and if you ment so say that wattage and lumens were the same thing your wrong, the 65 watts he or she has will do more than keep the plant alive... just not much more, and zoocick the difference your seeing between the two could possibly be because the two lights might have different light spectrum outputs cfls have a wide range of light wavelengths from daylight spectrums to cool blue spectrums