first things first get the temp up into the 80s+. baby pbass are ich magnets and the temp helps to stave that off.
second for fastest growth at that size i use quarantined guppies, just keep them swimming with him until he packs on the pounds. id keep him in feeders until at least 4" or so. after hes beefier try the dmack method of training onto prepared:
1. make him recognize the food comes from you by dropping a single feeder at a time and waiting till he eats that one before adding another. eventually hell be crashing the surface as soon as they drop in
2. start "faking him out" by chucking a chunk of whatever it is you want him to eat between feeders. something like feeder-feeder-prepared-feeder-feeder-feeder-prepared.
3. the first couple times he will spit it right out but eventually hell eat it. then increase the frequency of the prepared food in the pattern until hes eating it like a champ
as far as growth, on feeders and kept around 85 degrees expect that little dude to be 6" and too big for the 30 in only a couple months. 12" to mature in just under a year. when i grew out my last mixed batch i started the 5 of them in a 10G at 85+ degrees with constant a guppie supply and weekly 80% water changes. most went from 2" to 6" in a month and a half with the exception being the orinos and xingus who went a little slower ....
to give you an idea of growth rates, my zullies that are a year old in a week are starting to pair up and get schlexxy already
