Sturgeon, are divided into two categories: Acipenser and Huso. Kaluga and Beluga caviar are among the Huso fish. Beluga caviar is more expensive than Kaluga. Now we will describe each of the sturgeon. Sturgeons, also known as sturgeons, belong to the sturgeon family, a rare aquatic species with a history of several hundred million years, dating back to the Jurassic Age; And in the process, they evolved and have reached us today. The number of sturgeon species is divided into 27 species and subspecies in the world, of which 5 species live in the Caspian Sea; This sea alone contains 93% of the world's sturgeon reserves. Sturgeon in the category of aspirators are divided into the following 6 species: -Acipenser Persicus -Acipenser gueldenstaedtii -Acipenser Nudiventris -Ozone or Sevruga or Acipenser Stellatus -Berry or Acipenser Baerii -Acipenser Schrenckii Among these, three species of " Acipenser Persicus", " Acipenser gueldenstaedtii " and " Acipenser Nudiventris" are known as Sturgeon or Astra (Asetra). 
Kaluga Caviar Wiki
In wiki describe Kaluga caviar . In this section we describe some kind of sturgeon fishes: Acipenser Persicus (Qarabrun): The name of this fish means "black nose" and it is known because of its appearance. This fish is the best type of sturgeon in the world, which has recently been recognized as an independent species and, incidentally, is also a native species of Iran. Qarabrun meat is white in color and has less fat than other species. The very delicious taste of its caviar has doubled the charm of this fish. The caviar of this fish is in the color range of golden yellow to dark brown and its production in different environments takes between 8 to 10 years. If this caviar is produced under ideal conditions, it will give a fresh walnut flavor. Acipenser gueldenstaedtii: The name of this fish is named based on its different appearance and means "hollow head" .In most cases, it is similar to Acipenser Persicus (Qarabrun) fish, and the only difference is that the meat is yellower and has a weaker taste than Qarabrun. Acipenser Nudiventris or ship: The name of this fish is derived from its Latin and scientific name and has similar characteristics to other sturgeon, including Acipenser Persicus, but the differences between this fish and the two sturgeons above, can be attributed to the fact that this species is not farmed (for economic reasons) and also He pointed out the small size of its caviar grains. 
Sevruga: Ozone means "long nose" and its color spectrum varies from light gray to dark gray and sometimes black. It is not a farmed fish and its caviar has small grains and delicious taste that need 6 to 8 years to produce. Acipenser Baerii: The name of this fish, like Acipenser Nudiventris , is derived from its Latin name. It takes about 4 years to produce caviar, which is one of the smallest types of caviar. The caviar of this fish is seen in dark gray to black colors. This fish belongs to the waters of northern Russia and is ideal for farming environments due to the short time required to produce caviar. 
Acipenser Schrenckii: The original name of this fish is shrinki, which is the latest type of aspirators. This fish is specific to China and needs 6 to 7 years to produce caviar. From the combination of this fish and kaluga fish, the hybrid species Dauricus Schrenckii has been created. Beluga: This fish, which is known in Iran as elephant fish, has the largest, most expensive and rarest type of caviar. The maximum length of life, weight and length are: 80 years, ten and 6 meters, respectively. After each spawning, it starts spawning again after about 2 years. Between 10 and 15% of the weight of this fish is caviar. Sturgeon that takes about 12 years to produce in a breeding environment and its color range varies from light gray to dark gray and even black. 
Kaluga: This fish, which belongs to other species of the Husso family, is similar to Beluga in all respects, but has a similar appearance to Astra. It is found in the Amur River in China and, as mentioned, hybrids have also been produced from it.
Kaluga Caviar VS Beluga
Kaluga hybrid black caviar is one of the best and most prestigious dishes in the world! It has an extremely rich and Walnut taste with that legendary and famous sea wave. This caviar explodes with the taste in your mouth. Beluga hybrid caviar is a hybrid cultivar that combines Huso sturgeon and Acipenser Baerii treated by Caspian saltmongers. ... In this way, Beluga Hybrid combines the size and taste characteristics of Beluga with the stability and production speed of smaller Siberian sturgeon caviar. Kaluga Fusion Amber Caviar This colored amber rye is rich in a combination of Kaluga sturgeon (Huso dauricus) and Amur sturgeon (Acipenser schrenkii), which is distinguished by its hard, hard-boiled egg eggs and large, soft butter flavor. Kaluga is one of the largest families of sturgeon. Like the slightly larger Beluga, it spends part of its life in salt water. Unlike beluga, this fish has 5 main rows of crustaceans, nail-like teeth in its jaws, and feeds on salmon and other amur fish. 
Kaluga hybrid caviar, often referred to as the "Beluga River", is a sustainable response to the endangered population of Beluga or European sturgeon. In this way, the consumption of Kaluga caviar is repeated, and for some it may even go beyond the exquisite culinary experience of illegal caviar. The variety of Ossetra caviar in terms of taste, size and pigment characteristics can make any dining experience unique. ... Compared to the more delicate Beluga pearls, the oyster sturgeon's rope is smaller, firmer, and can range from bright golden colors to various shades of brown.