Sturgeon are long, bony, scale-less fish that live in subtropical, temperate and sub-Arctic rivers, lakes and coastlines. The name sturgeon actually refers to 27 different species that fall under the Acipenseridae family and the evolution of this fish dates back to the Triassic period about 245 million years ago! Fossils that have been found around Eastern Europe /Asia and North America have shown that this species of freshwater fish has barely changed in appearance over time, making it one of the most primitive species around. Today, many people raise certain types of sturgeon in their ponds. One of the most common sturgeons found in ponds is the Diamond Sturgeon (Acipenser gueldenstaedtii). But before you decide to get a diamond sturgeon for your pond, you should know a bit more about the species and the care that they require to live a long and healthy life:
Origin of Sturgeon:
This species of sturgeon is native to the Caspian Sea, Black Sea and Azov basins in Europe. Diamond sturgeons are anadromous which means they are born in freshwater, spend the majority of their lives in the sea and then returns to freshwater rivers to spawn. Common spawning sites of wild diamond sturgeon are the rivers Ural and Volga from the Caspian Sea and the rivers Danube and Riono from the black sea.
Sturgeons are some to the largest freshwater fish found in the world. While they do grow a bit less when kept in a pond, their full size at maturity is still very impressive. Diamond sturgeons raised in a pond can reach lengths of 1.25 meters and weight up to 15kg.
Sturgeon require a lot of swimming space due to the great size they reach as adults; This is why they should only be kept in large ponds with a capacity of at least 10,000 litres, NEVER an aquarium. Well, unless you have an aquarium of that size and volume of course - this is very rare to come by in the aquatics hobby.
Given you have a pond of 10,000+ litres; diamond sturgeon will be a great fish to consider. Two other vital factors you must have fulfilled are strong filtration system as well as pond equipment that will provide plenty of oxygenation to your water. Natural ponds with stagnant water will not have the pristine water conditions that diamond sturgeon need to survive. Diamond sturgeon must have very well oxygenated water at all times but especially during the summer months. Having a waterfall or an air pump will be the best way to make sure this requirement is met. It is important to remember that this species naturally inhabits clear rivers with a strong flow of water, so it is best to try and replicate these conditions. This is where pond filters come into play. A good pond filtration system will keep your water clear and moving. Remember, if you cannot see the bottom of your pond, filtration is likely not suitable. Plus, sturgeons reside at the bottom of the pond, so you will want to make sure you can see them!
It is also recommended that there be at least a small shaded area of the pond. If the sun is shining directly overhead, pond water can heat up quite quickly; sturgeon cannot tolerate warm water for a prolonged period of time. Shade will give them an area of refuge until the pond temperature decreases. The optimal temperature for diamond sturgeon is between 5 and 18 degrees Celsius. Pond temperatures above this can cause some problems and you may even find your sturgeon gasping for air at the surface. Warm water contains less oxygen than cold water, and as mentioned above, sturgeon will not do well with this water quality.
It is also worth noting that anything that reduces water circulation and oxygen exchange between the air and your pond will cause problems for sturgeon. Blanketweed that sits on your water surface can cause this disturbance and will need to be treated as soon as possible.
Substrate and Pond Plants:
Diamond sturgeons do not require an environment with a substrate. But, if you choose to have a substrate in your pond, it should consist of a soft material that will allow your sturgeon to safely root around without causing damage to their long snouts. A thin layer of sand or smooth gravel would be the ideal choice.
As far as pond plants are concerned, it is recommended to use them sparingly. Smaller plants will be easily uprooted while longer plants might tangle up the active sturgeon. The best option would be floating plants. These will not interfere with the fish’s activity and will even provide them with a source of shade.
The best diet for diamond sturgeon will contain a high percentage of animal-based protein (like fishmeal); the minimum protein content should be 40%. A good quality sturgeon fish food, like AllPondSolutions pellets, will also have a mix of carbohydrates, fats, mineral salts and vitamins. Diamond sturgeons are a very fast growing species and the large amount of protein in their diet will encourage healthy growth to its fullest potential.
Despite their tough looking outer appearance, sturgeons are actually quite delicate species. Many medications used to treat robust pond fish, like goldfish and koi, will not be suitable for use in a pond that diamond sturgeon live in. They are very sensitive to a lot of medications, those that include traces of copper and formalin can poison your sturgeon. This being said, the best treatment method that is safe for all pond fish is salt. Sturgeons have a very high tolerance for salt because this species naturally migrate to and from more brackish water in their life. So for issues like parasites, a good pond salt is your best resolutions.
Diamond Sturgeon are a peaceful bottom-dwelling species that will happily live amongst each other given that there is enough space and filtration in your pond. When choosing other fish for your pond, keep in mind that sturgeon are carnivores and very small fish will get eaten. Larger fish that will not fit in their mouths, like koi carp, will be perfect companions.