Serge explains us the realization of his garden pond
Construction of the pond
The pond is 50 cm underground and 40 cm above ground. All around, the earth slopes gently down to the level of the garden soil.
Advantages: less digging; use of the digging soil to make the slope; creation of a small height that breaks the monotony of the flatness of the garden.
The characteristics of the pond are:
- Volume 10.000 liters
- Depth 90 cm (If I had to do it again, I would make it 1,20 m deep)
Near the waterfall the depth is less: first a step of 40 cm on which I put water lilies, then one of 20 cm deep, where the water falls on large pebbles.
The bottom is a 8 to 10 cm thick slab poured in one go. The sides are made of 15 cm cinder blocks. On the upper blocks are embedded concrete irons that form a belt that allows to resist to frost (obviously not Siberian frosts!). The top of the sides is finished with paving stone . The concrete is mixed with a water-repellent powder that makes it waterproof.
On 2 sides, between 2 cinder blocks, at 40 cm from the bottom, I left a hole of about 10 cm diameter made with a plastic bottle around which I poured concrete. These 2 holes go through the cinder blocks and allowed me to install a lighting of the bottom of the water with 12 volts 50 watts spotlights. 50 watts are a minimum because the water is not always very clear, unfortunately. A window is located on the pond side, in the water, and the spotlights are therefore behind, out of the water. At night, seeing the fishes and plants underwater is really the most beautiful effect.
On 3 sides I installed some planters to plant plants. I made them with the help of forms as well as the feet on which they are posed. My mistake: I installed all 3 at the level of the water. According to the type of plants, they must be at 0, -5, or -10 cm.
Of course I also have pots at the bottom of the pond for water lilies, oxygenating plants or others.
The water level of the pond is constant. Indeed, I installed a flush float that brings water when the level drops. Of course it is black and hidden by the vegetation; nobody notices it.
The filtration
The material comes from swimming pool stores. The water intake is at the bottom of the water opposite the waterfall. It is a plastic suction plug with a grid, embedded in the concrete of the bottom of the pond.
All the piping is flexible, in 50 mm. The pipe of the bung goes out on the side of the pond and under ground to join the pump. This pump is a dishwasher pump (flow rate about 3m3/hour) that I got from the dump. It is also possible to buy one from an appliance repair shop. They get them from the machines they throw away. I personally always have 2 in advance, just in case ...
A washing machine drain pump does not have enough flow (about 1 m3/hour). This pump has to work under load, so it is below the pond level. This pump flows into the sand filter (for swimming pools) which is buried, for discretion. It contains 75 kg of sand, which is a minimum for this volume of water.
The cleaning is very easy since it is provided with a handle which allows to turn a valve with 6 positions: filtration, cleaning of the filter, setting to the drain (or to the garden, in my case) etc. ....
The filter outlet goes to the waterfall above. It has 2 concrete basins whose edges are hidden by
The edges are hidden by millstones, one under the other, which allows the water to oxygenate well at each fall.
The fish
I have of course fishes, koi carps, river carps, roaches but I have something else that aquarists will find surprising : I put guppy, every year at the beginning of June, when the water reaches 19 or 20°C. I remove them in September when the water is only 15 or 16°C. At this temperature they do not die but they become numb. Of course, it is not necessary to go lower. I put 4 females and 2 males, adults, which are not long to reproduce. And as there is a lot of vegetation, the young are not eaten . In a few days I will remove them. There are about 150 of them . The water is currently at 18°C and yet the young are just born. They are very easy to recover with a fine mesh net because guppies always swim on the surface.
I tried with scalars but it did not work; they do not hold in cold water. With platy, it works but you can't recover them because they swim too much at the bottom.
