This is what worked for me very recently with my 3.5 in IT, took a week to get him on dry food only. Soak Thera +A or Tetra Bits with the Blood Worm in a minimal amount of room temperature tank water overnight in the fridge. Have two batches going for one am and one pm feeding.
At first he will ignore the dry food but eventually start eating it with the Blood Worm. After a day or two of him eating both just give him the dry food. If he's stubborn it may take a few days. Once he eating only the dry food break up some Carnivore to add to the mix.
In my case he went for the Carnivore right away, then I switched to broken up Hikari Food Sticks and he's been eating them like a champ. I've been feeding him twice a day and he's really bulked up fast.
Hope this works for you, may or may not take longer but stick with it, imo it's only a matter of time before he's eating dry only. Good Luck !