Hello FSM,
i don't think they are easy to photograph ...
What's about the problem with the "red eyes" when using flash? I'm photographing fishes - cichlids, snakeheads, catfish and so on - okay, they are moving with more or less speed ... but their eyes are most time pictured in a very natural way.
To do this with bichirs you have to find out the right angle to photograph (the tolerance is very small) or you have to use an extern flash unit (i do so).
But some species (Polypterus delhezi, to name one of them) do have a much more reflective retina - so it's very difficult to make pics without the "red-eyes-effect".
Another way is to photograph without flash - a possibility in a heavy-lightened tank without plants. But you can't avoid some noise (i hope i'm using the correct word in english) due to the higher ISO-levels and the pics won't be as sharp as those which were made using a flash unit.
Greetings
Uwe