Mine would eat anything that have a strong smell. Before it would only eat feeders and a month later to prepared food and then I was able to trian it to eat pellets. But it will only eat on type of pellets and that hikari massivore delite. Man I love this pellets!
We have one about 30 inches in a 135 gallon tank, eats thawed tilapia or pieces of shrimp. I just started feeding it with long plastic tongs. Although with a voltmeter I the highest reading received has been about half a volt, and that was with a slight tickling with the tongs.
Try some large earthworms,that usually gets them going,if it wont take them then check your water parameters.
King-el,your right Massivore delite is a great alternative to fresh foods,i would go as far as to say from a nutritional point of view its even better.