Australlian Knife Fish?

Question
I have a knife fish, not sure, but I think it's Australlian. I have done a lot of research on this fish, but can't find much. I have learned it is nocturnal, needs hiding places, is a meat eater. I have a 55 gallon tank, have 4 gourami (2 kissing, 2 blue), many plants because I learned early they all love the plants. I have a hollow log, ship, and cave for fish to hide in, as well as plant arrangements with rock walls, that the gourami. seem to love. My knife fish I am worried that he is not eating enough. I feed the fish a varied diet including live minnows, flakes, brine shrimp, tubifex worms. How does the knife fish eat? Is he a bottom feeder, scavenger, live food, hunter type? He also has this very weird thing he does. He will swim around the entire tank then real quickly go to top and go back down. Why does he do this? How can I be sure he is getting enough to eat? As soon as I put the food in the tank he will go into the ship or cave and only come out once the food is gone. I am at a loss with this fish. I love this fish. He is very graceful and beautiful and I love watching him. Yes I only feed the fish when lights are off so he can get some, but I don't see him eat.

Answer
Dawn,
knife fish are nocturnal and during the day they prefer to hide.
They also navigate by elecrical impulse and sometimes the lights and heater can interfer with them.
they eat whatever is available so they are all of the above that you mentioned.
Over time you may be able to coax him out more but it will take some doing.
Make sure to feed after the lights go out so he will have some food.
If you have further questions, just ask.