Frogman speaks the truth. I love giving Godric fish every now and again as a treat, but they can carry parasites at times, so I'm waiting until I have a free tank so I can start keeping some feeder guppies/minnows of my own.
You tank is VERY beautiful, but I'm a little concerned at the pebbles that are directly below the greenery. They're small enough for the axolotls to accidentally eat, and they look sharp which means they could be even more difficult or dangerous to pass through the digestive system. It's generally a golden rule not to have axies on gravel or small rocks because they occasionally like to take a bite out of everything.
But your tank is seriously awesome. They must LOVE all the hidey holes they get from the plants!
Also, I just noticed the snails. I think there's a bit of mixed opinion on whether or not they're ok to keep with axies, but I think there's a similar concern with the gravel; if an axolotl eats one it might not be able to pass the shell. See what other members think about it.