Which species are you referring too when you say Tilapia. Want to know so I can look into getting a pair for breeding. I'm also looking into breeding African Clawed Frogs as a feeder too.
Oreochromis niloticus or Oreochromis aureus. Both would work just as well. The aureus can handle slightly cooler temps, which is nice if you don't want to use a heater (as long as you don't keep your house freezing cold). Warmer temps would obviously increase growth/breeding. If you can get a hold of the increased growth rate strains (I think it's GIFT or Akosombo?), you'll get appropriately sized feeders faster. Either species will produce more fry than you know what to do with.
Just cull/freeze them once they get to the right size, then you can thaw them out when needed. Freezing does destroy some vitamins, but gut loading the fish, and/or supplementing them occaisionally should work fine. Or feed them live every so often.
If you're looking into frogs for feeders, look into some of the larger pond frogs. Keep in mind the amphibian aspect of Homalopsis buccata diet could be mostly tadpoles (pure speculation), so you'd need some larger species, otherwise they'll probably be ignored.
Xenopus has
caused Oral Dyskinesias in snakes, as well as being an asymptomatic carrier of Chytrid. Obviously when breeding frogs be careful, and try to reduce pathogen transfer as much as possible. Remove eggs right away, breed a couple generation in first, bleach/sterilize everything (there are protocols online for sterilizing amphibian enclosures), &c. Parasites will never be eliminated, but can definitely be reduced.
Or try frozen frog legs from the market?
Another option, albeit kind of gross idea (and any family/partner will kill you if you use the house blender) is to blend up whole mice (already dead!!!) and inject that into the food. It would probably be easier with whole fish, as you can inject it into the body cavity. Just a thought.