I have a winebarrel lined with plastic, that makes a great starter pond. I think it's better than plastic for an aboveground pool as the wood insulates against it getting too hot or cold. I have one goldfish in it, whenever I try to put friends in for him he kills and eats them (even if they are bigger than him ), so I have come to the conclusion that "Hannibal" is a sociopath. A mini waterlily, an iris and lots of other waterplants such as lysimachia and oxyweed.