I just read his thread about his pond. The link doesn't work out of his sig though.
Still I don't think you know what you are getting into with an arapaima. Its like housing and feeding a horse. You also have to consider how much it is going to cost to maintain, such as food. You have tons of time in the future so why not wait until you are a little older, have your own place, and have enough money to do it how you want it? You could do a tank like arapaimag after saving up and keep all the big tropicals you want. But yes, winters will be a problem as there is really no way other than a propane pool heater to heat the water. Unfortunately those cost in the several thousand dollars range.
