Sorry to hear about your loss, and that you had such a rotten LFS. I live in on the Indaina/Ohio boarder and here a 75 Gallon Reef setup (Complete, minue the LR is 960) and a 150 is 1600.00 so they LFS scamed up big time.
As far as the shark pup, I agree 75 is a good size to hatch him in, but even my LFS does not recommand a bamboo shark for anyone with less than 125, perferrable 150 gallon tank. I had one in 150 gallon tank that was hatched for years. Gave him to a friend on mine that had a 1500gallon tank when I moved.
At least mine was like having an aquatic dog