How to Build a Fish Pond
There is really only one thing that will stop you from fulfilling your dream, no water. You need a steady flow of water from a spring or an overflow to keep the water fresh in the pond.
Fish need fresh water coming into the pond to provide oxygen. Some people have set a sump pump up to do the same thing; you need a close source of electricity for this method. Install the sump pump at the edge of the fish pond, hook a hose about 4 feet long to the pump and secure it to a wooden stake.
Point the hose outward into the pond so that the water shoots upward and falls into the water, this creates oxygen for the fish. You may have a low supply of fresh water coming into the fish pond that won’t create enough oxygen to keep fish alive.
So if you can manage this hurtle you can probably build a fish pond. How do you know if you have enough water for a pond? If you have an area out back that is wet or soft year around then you have what it takes.
A good spring will produce water even in the driest months of summer. There are two ways to approach this! You can build the fish pond at the source of water or you can build it in a dry area and pipe the water to it. The spring area must be higher than the level of the water in the fish pond. If you are uncertain of this, get a transit or a laser level and check the grade.
The spring water must run down hill and at a pretty good rate so that it creates enough oxygen. Building the pond at the source will create enough oxygen for the fish. Why else do you need a steady flow of water? The hot sun evaporates water from the pond and will actually dry it up.
The water needs to be a certain temperature for fish to live. I build my ponds at least 12 feet deep, the deeper the better. A deep pond will keep the water cool on the bottom, you can put an object in the bottom to provide shade if you have something suitable.
Make sure it is environmentally friendly so it does not poison the water and the fish. Build a pond in amongst the trees or plant some willows for shade.