14 February 2008

How to hatch eggs

Menetaskan telur ikan nila. Hatching is taking care of eggs so that hatch. Eggs change shape from round become oval, finally length. In the same time, develop all organ, like eyes, tail, and other organs so that become complete larva.

Naturaly eggs incubated in parent mouth. In this method, eggs incubated in the hatching tube. In order to hatch, eggs has to handled well. Eggs handling consist clearing, treatment, accounting, stocking, nusering, and harvest.

Eggs from parent mouth isn’t clear. There are many dirties, like muds, skins, trush, and other dirties, also bad eggs. Bad eggs has white in colour. Good eggs has yellow in colour. In order to hatch well, all of dirty have to separate of them.

Skins, and trush separated by a sieve or hard scoop net, where eggs can out, whereas skins, and trush hindered. Bad eggs separated by little interstice (shiponed). Whereas, muds separated by change water. Except dirty, also eggs has diseases. For preventing it, eggs treated by methylin blue 0,2 ppm for 5 – 10 minutes.

Eggs stocked to the hatching tubes, but before eggs have to accounted, by volumetric system. Eggs entered to a small cup, then accounted one by one. A hatching tube can stocked 1.000 – 1.500 eggs/litre water. If a small cup are 500 eggs, for a litre water entered 2 small cups.

In order to eggs distributed in hatching tube, discharge has to regulated, don’t too fast, don’t too slowly. Too fast can destroy eggs, and it can cause larvas dead. Too slowly can’t stir eggs, and it can cause eggs in heaps, and hatch in low. Discharge can regulated by water tap.

During hatching, eggs have to cared. Muds, bad eggs, and other dirties have to out of hatching tube by siphoned. Discharge regulated by water tap in 0,6 – 0,8 litres/minutes. Except for distributing eggs, also current water for supplaying oxygen.

In 25 – 27 O C, eggs hatch in 5 – 7 days. Larvas has length 8 – 10 mm, and weight 0,02 – 0,05 grams will swim to hole in hatching tube, carry out through the hole, and hindered in trays. Harvesting is done in the trays, secoop net, the entered to pails.