My datnoid only eats live large goldfish feeders, 25+ at a time...everyday, skipping a day once a week.... we'll see how this goes. Best I can do is gut loading them with a variety of veggies, pellets before feeding.
The problems with large feeders is larger than thiaminase toxicity. The levels of copper used in goldfish farms is high enough to cause liver diseases in any predators fed a regular diet of these mass-raised goldfish.