\Who sells a 6" black arowana for $75? If this was a 75 gallon tank, that would even be a worst deal. Maybe the black knew how cheap your friend was selling him and commited suicide. Check out fishinabowl, they have black arowans for $150Uhhh.... What? Who said anything about a 75g tank? What does it matter if he was trying to sell it for $75 or $7500?