Equipment & Materials
You will be expected to provide all the necessary equipment to the school for them to be able to run their own 'hatchery' (if further advice is needed regarding acquiring equipment including possible suppliers please click here):
1) The eggs are placed within a tank. This tank will either be solitary (cooled by a specialised cooling unit) or part of a double tank unit (see figure below).
2) Ice packs/pump - If a double unit is used then ice packs will need to be used to cool the water in the tank not containing any eggs. Access to a freezer will be required for ice packs. Water is pumped using an aquarium pump from the tank containing ice packs into the other tank. The warmer water in the egg tank is re-circulated into the cooling tank to be cooled.
3) Cooling unit - specialised cooling units (usually used for beer!) can be used to control the water temperature (see photo below). The desired water temperature can be set on the unit and the water is pumped from and to the tank containing the eggs.
4) Egg grid - the eggs should be placed upon an elevated grid to allow water to circulate fully around them. The grid should allow the alevins to fall through once they hatch. A bed of gravel or small stones can also be used, but removal of dead eggs or alevins may be problematic.
5) Thermometer - water temperature is key to the survival of eggs and alevins. The thermometer should be placed near to the eggs and in a position where it can easily be read.