I find it so interesting when people start asking questions in the forum about someone elses post and start making assumptions about the shark in question. Yet nobody has asked me and I'm the one with first hand knowledge about that particular shark. Here's the secret to keeping your sharks from growing like a bad fungus and yet keeping them healthy:
1) Only feed once every 5 days but enough to satiate. Too many shark owners totally dig watching their sharks eat to the point that they don't realize that the over feeding will increase their metabolism and growth rate. As long as your shark maintains it's normal body confirmation and behaves normally, it's safe to assume you are meeting its nutritional needs. (And always add vitamins to the food!!!)
2) Keep the water temp. in the low 70's (for tropicals). Warmer water will increase the metabolism as well.
As far as stunting their growth is concerned and any renal/liver damage I can only say that the one Long Beach had a couple years ago was purchased from me and was kept by me under the same conditions as the one I have now. From what I understand they gave it to OK Aquarium, so OK would be the ones to ask about it's current health status. I've donated quite a few sharks to aquariums over the years after keeping them in my tanks. All of the ones I was able to keep track of seemed to live on nicely.