When we were faced with a simular situation, we found a new home for our beloved dog, it was a hard choice, but we have visited "Snickers" and he seems just as happy with his new owners as he did with us and we have our freedom. Win, Win. As for the
fish, If you have some expensive fish, I would advertize on Criegs list and find them new homes also. You could always replace them when you return if you wanted. With our home, we found short term renters. My wife is a nurse and knew some traveling doctors that needed a furnished home for 6 months so we rented to them. Paid for our trip and then some.