I've witness my JD get chew up and die because it couldn't be digest down..
It was a horrible death.. it got chew on badly....... since then.. i have limit the size in my tank so roughly only 5 inches minimum vs. a 22inch arowana... any small and well... its food/waste of fish...
Tried it with my real Ca's. A few parachromis and amphilophus.Wasn't so good for the FH had to move him to his own tank. My loiselle are smaller than the fh, but owned it.