My tank is about 50 litres, circular blue plastic drum that I can take off the boat if I am not fishing live eel or joey mack. I have a Rule 360 bilge pump on a 6 foot hose that goes overboard to pump fresh water into the tank, the outlet is a sink plug hole fitting about 4 inches below the tank's rim which overflows onto the self draining deck. The water is pumped through a pipe fixed around the rim of the tank with holes drilled in it to spray the water onto the surface of the tank to add a bit of oxygen to the fresh water.
The colour of the tank is important to me as I have noticed that if they are kept in a blue one the blue irredescent line down their flanks really sparkles. Kept in white, or yellow and the line dulls. I keep my eels in Yellow 1000 litre tanks at home and as soon as I put them on the boat tank that bit of blue really shines. They also seem placid when kept in yellow tanks and far more active in the blue one.
I can keep 200 launce / eels or a dozen joey mack in this size tank quite hapily all day and they come out fighting fit.
