peacock bass are very stubborn i just recently got my temensis on freeze dried jumbo shrimp and that took almost 3 months of starving and then feeding him just a little. when try putting some shrimp in the tank where the pump spits out your water it makes it look alive and the peacock bass might go for it (atleast thats what i did with mine)
I have my 12" peacock eating out of my hand and it took him a month to even eat frozen now he's great but the 5" mono just hasnt given in yet he looks skinny
Do you have other fish in the tank with him? Try freeze dried blood worms. I made the mistake of starving my kelberi, got really skinny. Got the kel eating normal and took shrimp a couple weeks later. Mono's (IME) are the easiest to convert.
I found out that starting them on pellet can be a lot easier if you have a smaller tank. That way the bass can always see the food. I had a bass that had never been fed fd or pellet before and it only took me a week. Other fish that pound pellet in the tank with them is the key.
im training my smaller pbass to eat pellets right now. I use a pipette and squirt a small amount of frozen blood worms (let it melt first) and as soon as the worms hit the water.. i throw some small sinking pellets. 2 out of 5 pellets that goes in usually gets mistaken as blood worms