After eggs are obtained either naturally or stripped from broodstock and fertilized, they can be transferred to a suitable incubator where they remain under controlled conditions at least until they become ‘eyed’. There are many different types of egg incubation systems, e.g., egg boxes, trays or jars. The appropriate type of incubator depends on the species to be reared. The EGG NURSERY table describes best conditions for successful breeding.

The field Nursery system gives a broad classification of the appropriate incubator for the selected species. A more specific description of the nursery system is availaible in the Details field where information can be added about the type of egg incubator, modifications, proper egg handling and egg treatment, water flow, and other recommendations.

The field Stocking density indicates a number for optimal stocking of eggs in the incubator. A variety of units for this value can be chosen from a drop down menu.

The field Main water source indicates the usual water source used for egg incubation. An alternative source is mentioned in the field Supplemental water source.

The fields Temperature, Salinity, pH, Oxygen, Hardness and Illumination indicate the range of optimal abiotic values for egg incubation.

The field Egg mortality indicates the egg mortality encountered during the complete incubation period until hatching, in percent.

The field Eyeing indicates the day-degrees needed until the dark pigmented retina is visible in the embryo. At this developmental stage, eggs can be manipulated in order to separate dead or abnormal developed eggs from the healthy batch, or eggs can be transferred to another incubator if required.

The field Time to hatch in day-degrees and in hours gives information on the time needed for larvae to hatch. Because time to hatch depends to a great extent on the temperature, the values presented here relate to the temperature regime as noted in the respective fields.

The Production/cycle field indicates the productivity of a broodstock in number of eggs/batch spawning, and the field Production/year indicates the total productivity of the broodstock in number of eggs/year.

The free text field Comments may be used for further relevant notes about egg incubation such as sorting and transportation and quality control measures or treatment against infection and parasites.