Another CK Feeding Question

[Dirty Old Man]

I have two knives that are too small to fulfill this idea @ the moment; but I'm sure in a year I'll be able to...
I was wondering if it woud be safe to feed them trout, s/m bass, l/m bass, or bluegill. I have a lagoon nearby in which they stock with these types of fish. Would these be acceptable foods for when the knives are full grown (or at least large enough to eat them?) It'd cut my cost down on their food consumption; I just don't know if it'd be safe for them to eat these types of fish (all of which are consumable by humans...and damn if those aren't good tasting fish...)

 

[Oddball]

I'd go with the trout and stay clear of the bass and sunnies because of their hard sharp ray spines.

 

[Dirty Old Man]

I'd go with the trout and stay clear of the bass and sunnies because of their hard sharp ray spines.

If I were to cut off their spines just before feeding would it be ok? I know they are boney fish and I don't know if their internal bones would be a problem as well. If not, then I'll be happy to stick with the trout.