my guess is that it was a water shortage or a temperature flux out of the ideal range of 70 to 80 degrees F during the day/60 to 70 degrees F at night during flowering that did you in, though the plant admittedly requires a ridiculous amount of light to be happy
it is a very fussy plant...if you don't meet those needs, fruit never sets, and flowers will always fall off...
took me a while to figure out i had to pollinate the plants myself indoors for the fruit to set nice too...
14/10 or 16/8 to answer your question though....
depending on the type of lamp you are using, it very well may be throwing your temp out of range...several elevations of readings should be sampled to get a better idea what the plant is really getting