i have 7 neon tetras that i have had for about 4 months but from the very first day i got them they just hide in one off my big plants and swin to the ship every so often and never go about 1cm above the gravel there colours look fine and they are eating, i throught that they like to stay in the middle of the tank. To you think they a scared of the other fish. I have 2 moonlights with are about 4-5 years old and very big.