May 3, 2012

Corydoras duplicareus @ Day 17

Corydoras Frys @ 17 days from Day One - Egg

Finally after a painful number of corrective actions, got to see the stage of free swimming frys eating external foods. Death rates have came down significantly to almost zero. The frys are much stronger and vibrant as well.

To date, i have at least 20 free swimming frys taking both brine shrimps and dry foods from 3 different hatcheries of different batches. About another 20 still taking york sac. And about a dozon left over eggs. Since cutting down on food to the adults, breeding has slowly ceased. This allow me breathing space to concentrate of growing the frys and a cleaner tank water.

During this period i have the hatchery expanded to cater for larger active frys. They are handmade of which the design i am proud of after many trials and errors. Is more fun than keeping the frys alive though the result is the goal.

Hatchery Requirements

- Will not topple
- Prevent foods from slipping through
- Side and under opening to support good ventilation
- Shock absorption internal and external
- Will not escape or eaten through gaps
- Easy to navigate the hatchery
- Easy to observe the frys
- Large enough room to support fry growth
- Cheap and easy to access materials
- Provide shade but avoid dead corner area
- Tank debris not easily stuck onto it

3rd May 2012


  1. you should try using an external breeder box, they are excellent! I've had great success with them, rarely loosing fry since started to use one. In Taiwan they should be really cheap too.

  2. thanks for the suggestion. I have seen those design which requires another air pump to works with it. I do agreed it should works well.

    The key is the ventilation and water quality control which i realized later as most of my earlier frys die from the poor ventilation of Guppy tank as the vertical slots seem do not allow sufficient water movements.

    Added two photos.

  3. If you run a canister filter, there is no need to run an air pump. Just hook an airline tube from the spray bar to the external breeder box. This will actually cycle more water into the external breeder box than using an air pump.

  4. That maybe too strong for the fry. Currently i only use air pump.