A garden pond can enrich the garden for people and animals. But if goldfish are to be kept in it, it must be of the appropriate size and depth. This is especially true if the fish are supposed to hibernate in it. Because the right dimensions are important for the health and safety of the fish stock.
Fish stock
Goldfish should at least be kept in small groups and will multiply with good care of the pond. If this is the case, sooner or later the fish stock in a small pond will have to be reduced. With a large volume, this is much less necessary.
Predators
Cats but also herons, foxes and other animals see a garden pond with goldfish as a potential source of food. A large volume gives the fish more opportunities to escape these predators.
layout
A bank area, different planting levels, parts of the garden pond lying in the shade and others from the sun illuminated - a large scope with a corresponding depth is also possible with extensive design options hand in hand. Several and different plants can be introduced, which in turn serve as food sources and hiding places for the fish. The optics also benefit from it.
cleaning
Since the equilibrium in the water is more stable with a large volume, the garden pond has to be completely cleaned and freed from accumulating sludge less often. However, a corresponding filter is an important prerequisite for this. As well as the regular removal of invaded dirt.
wintering
Small ponds of shallow depth can freeze over despite taking appropriate precautionary measures. In this case, the goldfish have to be caught in autumn and overwintered in the house. In a garden pond with a large volume, not only is the effort required for wintering less, it is also safer for the fish.
There is a simple rule of thumb when choosing the size of a garden pond for goldfish: you should plan at least three liters of water for every centimeter of length of a goldfish. For five goldfish, each ten centimeters long, that would be:
The rough calculation could look like this:
+ 1,000 liters for aquatic plants
+ 1,000 liters for any offspring and other aquatic life
= 2,525 liters
That sounds like a very large pond and the reserves have already been generously calculated. In fact, with a round pond shape, a diameter and a depth of 1.5 meters each would be sufficient to get this volume of water. The advantage of this generous calculation and the planned reserves is that the The equilibrium of the water is more stable and thus the cleaning effort is reduced - but the safety is increased.
In addition to the circumference, radius or diameter, the depth of the pond naturally also plays a decisive role. For one thing, it affects the volume of water. On the other hand, a greater depth offers better retreats for the goldfish and thus protection from enemies. It also makes it easier for the fish to overwinter. The absolute minimum depth for goldfish is 80 centimeters. In summer there are still cooler water areas in the depths. The garden pond cannot freeze completely in winter. However, a depth of 1.0 to 1.5 meters is better. With a garden pond, such a depth means:
First, the area of the respective shapes is calculated and this is then multiplied by the depth of the section.
So:
Side length a x side length b = area (A)
1 meter x 2 meters = 2 square meters
In order to calculate the volume from this, the depth is multiplied by the area.
A x depth = volume
2 square meters x 1.5 meters = 3 cubic meters
Radius² x Pi = area (A)
(0.75m x 0.75m) x 3.14159 = 1.76715 square meters
For the volume of the round section, in turn, the area is multiplied by the volume.
Area (A) x depth = volume (V)
1.76715 square meters x 1.5 meters = 2.65072 cubic meters
In a two meter long and one meter wide pond, the long semiaxis (a) measures one meter, the short semiaxis (b) 0.5 meters.
a x b x Pi = area
1 meter x 0.5 meter x 3.14159 = 1.5708 square meters
For the volume, this result is multiplied by the depth of the section, as with the other shapes.
Area (A) x depth = volume (V)
1.5708 square meters x 1.5 meters = 2.3562 cubic meters
Finally, the cubic meters only have to be converted into liters. One cubic meter is equivalent to 1,000 liters. A volume of three cubic meters therefore holds 3,000 liters.
Tip: It should be noted, however, that these are only approximate values, as the pond usually tapers downwards - i.e. becomes narrower. If you want to be sure that there is enough water for the desired number of fish, you should make the side lengths a little larger and set the target volume a little higher.
The garden pond is usually designed in such a way that it tapers towards the bottom. This also reduces the water volume in the depth. If the pond freezes over from above, the goldfish not only have less space and water available, but also less oxygen. This in itself is not a problem, because the slowed metabolism during the winter also slows the breathing of the fish.
However, if the number of fish is large, the pond continues to freeze over or aquatic plants in the pond also consume oxygen instead of producing it, this condition becomes dangerous. In fact, most fish don't freeze to death in ponds, instead they suffocate. To reduce this risk, the garden pond should be prevented from completely freezing over - regardless of how big and deep it is. The following measure is recommended for this:
volume
The following applies to the volume of the garden pond: the larger, the better. And that in several ways. A more stable biological equilibrium can be established in a large garden pond. Impurities such as fallen leaves, leftover food, fish droppings or dead plant parts are less of a problem than in a small pond. In addition, large garden ponds also have other advantages to offer:Fish stock
Goldfish should at least be kept in small groups and will multiply with good care of the pond. If this is the case, sooner or later the fish stock in a small pond will have to be reduced. With a large volume, this is much less necessary.
Predators
Cats but also herons, foxes and other animals see a garden pond with goldfish as a potential source of food. A large volume gives the fish more opportunities to escape these predators.
layout
A bank area, different planting levels, parts of the garden pond lying in the shade and others from the sun illuminated - a large scope with a corresponding depth is also possible with extensive design options hand in hand. Several and different plants can be introduced, which in turn serve as food sources and hiding places for the fish. The optics also benefit from it.
cleaning
Since the equilibrium in the water is more stable with a large volume, the garden pond has to be completely cleaned and freed from accumulating sludge less often. However, a corresponding filter is an important prerequisite for this. As well as the regular removal of invaded dirt.
wintering
Small ponds of shallow depth can freeze over despite taking appropriate precautionary measures. In this case, the goldfish have to be caught in autumn and overwintered in the house. In a garden pond with a large volume, not only is the effort required for wintering less, it is also safer for the fish.
size
There is a simple rule of thumb when choosing the size of a garden pond for goldfish: you should plan at least three liters of water for every centimeter of length of a goldfish. For five goldfish, each ten centimeters long, that would be:- 5 fish x 10 centimeters per fish = 50 centimeters fish length
- 50 x 3 liters = 150 liters
- the first 1,000 liters should come from aquatic plants
- Goldfish can grow to be 35 centimeters long, depending on the type of cultivation
- Goldfish spawn contains 500 to 3000 eggs
The rough calculation could look like this:
- 5 fish x 35 centimeters length = 175 centimeters fish length
- 175 x 3 liters per centimeter = 525 liters
+ 1,000 liters for aquatic plants
+ 1,000 liters for any offspring and other aquatic life
= 2,525 liters
That sounds like a very large pond and the reserves have already been generously calculated. In fact, with a round pond shape, a diameter and a depth of 1.5 meters each would be sufficient to get this volume of water. The advantage of this generous calculation and the planned reserves is that the The equilibrium of the water is more stable and thus the cleaning effort is reduced - but the safety is increased.
depth
In addition to the circumference, radius or diameter, the depth of the pond naturally also plays a decisive role. For one thing, it affects the volume of water. On the other hand, a greater depth offers better retreats for the goldfish and thus protection from enemies. It also makes it easier for the fish to overwinter. The absolute minimum depth for goldfish is 80 centimeters. In summer there are still cooler water areas in the depths. The garden pond cannot freeze completely in winter. However, a depth of 1.0 to 1.5 meters is better. With a garden pond, such a depth means:- no complete freezing even in cold winters
- more stable temperatures throughout the year
- It is still easy to clean and vacuum pond sludge
- greater security of the fish from predators such as cats or herons
- Design of different sections and introduction of different plants possible
Calculate garden pond volume
The bigger the better - that much is now clear. But how can the water volume in a garden pond be calculated at all? Because unless it is a perfect cuboid shape and the pond may also have sections of different shapes, the calculation appears difficult or even impossible. However, the solution to this is very simple. It is not the entire garden pond that is calculated, but the respective sections.First, the area of the respective shapes is calculated and this is then multiplied by the depth of the section.
Squares and rectangles
For the area of rectangles and squares, only the side lengths are multiplied together.So:
Side length a x side length b = area (A)
1 meter x 2 meters = 2 square meters
In order to calculate the volume from this, the depth is multiplied by the area.
A x depth = volume
2 square meters x 1.5 meters = 3 cubic meters
Circles
For the area of a circular shape, the radius or half the diameter is first squared and then multiplied by the number pi.Radius² x Pi = area (A)
(0.75m x 0.75m) x 3.14159 = 1.76715 square meters
For the volume of the round section, in turn, the area is multiplied by the volume.
Area (A) x depth = volume (V)
1.76715 square meters x 1.5 meters = 2.65072 cubic meters
Ellipses or ovals
Elliptical or oval shapes are often chosen for garden ponds. The area is calculated by multiplying half of the axes together and by the number Pi. To calculate the semi-axes, the two side lengths are only halved.In a two meter long and one meter wide pond, the long semiaxis (a) measures one meter, the short semiaxis (b) 0.5 meters.
a x b x Pi = area
1 meter x 0.5 meter x 3.14159 = 1.5708 square meters
For the volume, this result is multiplied by the depth of the section, as with the other shapes.
Area (A) x depth = volume (V)
1.5708 square meters x 1.5 meters = 2.3562 cubic meters
Finally, the cubic meters only have to be converted into liters. One cubic meter is equivalent to 1,000 liters. A volume of three cubic meters therefore holds 3,000 liters.
Tip: It should be noted, however, that these are only approximate values, as the pond usually tapers downwards - i.e. becomes narrower. If you want to be sure that there is enough water for the desired number of fish, you should make the side lengths a little larger and set the target volume a little higher.
Pond size and overwintering
Garden ponds that are as large and deep as possible offer protection during the winter and allow the goldfish to remain outdoors even during the cold season. But there's more to that, because it's not just the low temperatures that affect the fish.The garden pond is usually designed in such a way that it tapers towards the bottom. This also reduces the water volume in the depth. If the pond freezes over from above, the goldfish not only have less space and water available, but also less oxygen. This in itself is not a problem, because the slowed metabolism during the winter also slows the breathing of the fish.
However, if the number of fish is large, the pond continues to freeze over or aquatic plants in the pond also consume oxygen instead of producing it, this condition becomes dangerous. In fact, most fish don't freeze to death in ponds, instead they suffocate. To reduce this risk, the garden pond should be prevented from completely freezing over - regardless of how big and deep it is. The following measure is recommended for this:
1. Use a thick styrofoam sheet or, even better, a special ice preventer for small garden ponds. For larger ponds, it should be several styrofoam sheets or an ice preventer with an air pump.
2. If a styrofoam plate is used, a hole should be cut in the middle and a piece of garden hose should be passed through. The hose should be long enough that it almost reaches the ground but is not stuck in the ground.
3. To prevent the styrofoam from floating too easily on the water and thus lying over the ice, it may be necessary to weigh it down. For this purpose, there are heavier, larger stones that are lightly pressed all around into the styrofoam or glued to it. However, special weights can also be used.
Tip: Styrofoam or ice preventer should be applied to the pond as early as autumn in order to provide protection in the event of early onset of night frost.