I've heard this story and experienced this story a dozen times. He'll probably puke it up and make your tank absolutely filthy in a day or so. Be ready to do a massive water change and cleaning.
Felix said it best...don't have tankmates, just future meals
My old RTC at fish bigger than this and he literally couldn't swim but never puked, he just hid up and chilled until he was done digesting it
To OP I'm guessing by now you have realised that large catfish eat everything eventually, I think you need to decide to keep 1 large cat solo or trade/sell them :/ I had to do the same thing, it was hard but much better in the end
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