Pretty fishes!!

Im new to blender. this is my scond project…
it feels like its missing something. ANY imput would be appreceated.

That looks like a great model for your second project!

The texturing on the tank seems a little off and your lighting looks weird.

You should also add some stuff to the tank (plants, buildings, etc.)
Another nice addition you could do is put the tank some where (texture the plane it’s on is a good idea).