How often feed over 12" Pseudacanthicus sp?

[Proteus]

Im starting to doubt myself am I underfeeding my L24? Been feeding it scallops or raw shelled cut up shrimp once a week maybe 1 inch square i dont know if I should be offering it more days, kens earthworm sticks maybe 6 a day, commerical size alage wafers every other day. It even relishes scavening for all tetra flakes that makes it to the ground after messy tetras/barbs/loaches dont eat after few minutes. Have had it for a month. I love this pseudo. It now likes the PVC pipe I put in it for it. Am I missing something in its nutritional needs? Its definitely over 12" for sure. Might be at the 13-14" with tail streamers not included.

The L114s in another tank are greedy with their shares. No doubt they like what Im feeding them. 6", 4.5" and 3"

Should I start soaking the shrimp in some type of supplement?

[Proteus]

Its nibbling on the shrimp piece in peace and quiet from its tankmates in the PVC it dragged it back inside to eat without being harassed by the barbs. The barbs act like I never feed them. They have no boundaries whatsoever everyones slated to be moved out to the 75g so it will only be the loaches, clouded archerfish and this guy/gal the pvc is 4" big in diameter i spray painted it with krylon fusion for plastic months back letting it cure for a month as it was supposed to be for the loaches to chill but guess its its hideaway now. It likes the 4 way to spread its fin in the middle while looking out of the one of the holes. Its at least 13-14" long for sure