I have 2 fire eels and a golden dojo loach in my tank with other fish, and when I feed frozen blood worms, it's fun to watch. I put the cubes in a small bowl of water til it melts, then I pour them down a clear plastic tube so the current doesn't scatter it too much. The dojo will come up to the blood worms and surround it, while eating. But that doesn't work, the fire eels either slip under or over him and sucks up all the blood worms like vacuums. The fire eels are now about 9 inches, and the dojo about 8 1/2 inches.