Most every other site shows a minimum of 25-30 gallons so not sure why MarineDepot is showing 100 gallons. The only reason I can think of is they do need a fair amount of space for hiding and playing in and out of the rocks. He is only 3 inches right now and should get to 4 inches total.
I have heard so much controversy around the Potter's Angel. How only 5% only live past 1 month and how they only have a 50% chance of survival and if they get stressed it can be fatal so I don't want to send him back to a small holding tank at the LFS
Well I have good news anyway, I am just about to purchase another 75 gallon aquarium to house him in. I can't help myself and can't bring myself to give him up. I have pictures of him and will post them tonight..
I do appreciate everyone's advice and help.