I believe the only reason he's a bit scared now is because he's not used to you, or being handled in the same way as you do

Just give him time, talk to him by the tank when you feed him or watch him and he'll get used to your voice and start associating it with food = good thing

In no time he'll be happy to have you close

You could try teaching him gradually to start eating from your hand first, which again would let him get more used to you and your hands
