BGK are not the fastest growers so in the future the size difference might be concerning. my bgk has been growing at about 4 inches a year, whereas i had an aro that grew 3-4 inches a month. my bgk is the least picky eater in the tank, he'll eat anything i throw in there from flakes, food sticks, to frozen and live foods. They're super cool and you should get one even if it doesn't go into that tank.