This might be of interest to those thinking of using a stock tank for making a pond. This 150-gallon tank is sort of a hybrid. For 20-years, it was used to overwinter pond plants and as a holding tank for new fish or rescued fish. Over time, 'morphed' into a pond/aquarium based upon what I moved into it. It sits in our sunroom and houses pond and aquarium plants. The trees in the water are Red Mangroves. You can see their distinctive prop roots extending from the trunk. The three plants growing emersed are Amazon Swords, Anubias and Water Sprite which is growing out and over the side. One very luck betta and a few upside down catfish live in the tank for now. Sometimes one or two small goldfish find their way into the tank too. They are usually rescues waiting for a home. The tank is heated and filtered with two, air driven sponge filters. Simple and very effective. I retired and drastically downsized now only keeping this tank, a turtle pond, an Archerfish (who lives in a palatial suite), one garden pond and a porch pond. That's it. I am willing to share any lessons learned...and there are many! 
Happy New Year!
Stephen
Happy New Year!
Stephen
