The majority of sturgeon species are best suited to, and are happier in, water temperatures under or around 20 degrees C. Within a pond of a minimum 2000 gallons with the exception of Sterlets which can be comfortably housed in 1000 gallons, the important fact to bear in mind is these fish grow very quickly and to a large size.
Small sturgeon are better in cool temperatures of 10-15 degrees C for optimum growth. As their size increases to around 3-4" they can then sustain growth and tolerate temperatures up to 22 degrees C, and are more able to cope with the lower oxygen levels. Over this temperature the food intake will slow down and metabolic overload may occur as most sturgeon will not eat in temperatures of over 26 degrees C.
Ideal water conditions are;
Ammonia 0.0mg/l
Nitrite less than 0.25 mg/l
Nitrate less than 150 mg/l
PH should be above 7.0 and below 9 (i.e. low alkali)
High oxygen levels, more than 6mg/l
and cool water temperatures less than 26 degrees C
Sturgeon require quality food and lots of it. It should have a high oil content (16% fish oil) but a low vegetable and cereal content. Small amounts of wheat or soya used as a binding agent are acceptable but the protein content - 40%+ - should be fish meal based and not cereal based.
Sturgeon cannot digest plant material and anyone selling sturgeon saying "they clean the pond" are very much mistaken. This common myth has derived from the fact that sturgeon, like carp, will root around in the pond silt sifting out the natural insects and larvae that live within the silt layer. They are not actually eating the silt, as there are no fish that do this.
Getting these requirements correct as a whole should ensure that you have happy and healthy sturgeon.
