About the frozen ship thing, do as you wish i just don't see how eating and digesting sharp clam shells is any better than frozen shimp that literally melts after 2 mins. A far as the fish i kept, I sold my largest fahaka after a year, which was about 3 years ago... The person that bought the fish from me lives close so I go to check it out every once and a while, it's fully grown now and it beautiful... He uses the same method I did. I'm not saying it's the best, and I'm not sure it will work for every fahaka... i do know that there is a four year old fahaka they is still going strong on this diet.
As for why they are not popular, i know that in Toronto they are very difficult to come by, once every two years they pop up... this might be why, not exactly sure.... I do know that people are alittle sketchy when having to designate an entire tank to one fish... this would be no problem for me though cu they are entirely worth it.