I got one of these recently, at likely just under three inches in length. He was quite emaciated, and ate roughly 20-25 small guppies in the .5-inch size range during his first couple weeks. I would not normally feed that way, but I needed to ensure he had food available while I was absent for work, and hadn't yet tried him on prepared foods.
Today, roughly three months later, he is a bit over 4 inches in length; quite a slow growth rate compared to other predatory fish I have raised, but perhaps since this one only reaches 8 - 10 inches the slower growth rate is to be expected.
At his current size, he will consume 12 or 15 of the small shrimp-like crustaceans in Hikari's frozen Ocean Plankton at a sitting before his interest even begins to wane. These shrimp are generally about half inch in length. Now that I am home for awhile, I am feeding him heavily, so he also gets an assortment of fd or frozen small krill, assorted predator-formula pellets, small earthworms, freshly-swatted Deer Flies (often containing a generous helping of human blood!), and other foods.
Massivore pellets are much too big for him at this size; I would break them into thirds or even quarters if I were offering those. Otherwise, he grabs a large chunk of food (like a whole Massivore) but chews and shakes and worries it until it breaks down into swallowable pieces, and this creates a lot of waste and unnecessary pollution in the tank. Keeping the food items small enough to be easily swallowed whole keeps the tank a lot cleaner. He was a very easy fish to switch from live to prepared, basically no training required.
At four inches, a single Massivore broken up and easily swallowed would be a pretty big meal, IMHO. I'm by no means a "power-feeder".
