Sunday, September 23, 2007

How to hatch brine shrimp

Newly hatched baby brine shrimp are an extremely important food for betta fry. This is the food that will get your fry growing strongly and quickly. I start feeding baby brine shrimp from about the 3rd or 4th day after free-swimming alongside microworms and vinegar eels. Then I gradually stop feeding the smaller food as soon as I am confident that most of the fry are taking the brine shrimp. The most nutritious part of baby brine shrimp is the yolk sac and it is important that you feed the brine shrimp to your fry before this yolk sac is used up. This means using the brine shrimp within about 12 hours of hatching.

To get brine shrimp eggs to hatch successfully you need the following conditions:
  • Salinity of approx 15 ppt which is equivalent to a specific gravity of 1.011
  • Temperature 28 deg C
  • pH 8.2 - 8.6
  • Sufficient aeration to keep the eggs in constant motion
  • Good quality, fresh eggs. If the eggs you buy aren't in a completely sealed package at least make sure your supplier has a reasonably high turnover to ensure the eggs are fresh.
This is how I hatch bs eggs. You need the following bits and pieces:
  • 2 x 1.5 ltr plastic drink bottles (start one about 12-18 hours after the other)
  • Small airpump
  • Some airline (no airstone)
  • Airline splitter/manifold (you need 3, one for each bottle and one to keep water circulating around the heater)
  • Heater
  • A container that will hold the two bottles plus the heater
  • Rock salt (no additives or caking agents)
  • Sodium Bicarbonate (Baking Soda)
  • Magnesium Sulfate (Epsom Salts)
  • Plastic funnel (makes it easier to fill the bottle)
Here's what you do:
  1. Make a hole in one of the dimples at the bottom of the bottle large enough for the funnel to go through.
  2. Put the bottle upside down, resting on it’s cap in the container with the heater
  3. Fill the container with water so it covers the heater and comes part way up the bottle. The bottles don't have to be completely submerged. An inch or two is sufficient to keep the bottle warm.
  4. Put 6 tsp salt, quarter tsp sodium bicarbonate (or the required amount to raise the pH to 8.2), quarter tsp Epsom salts, about a quarter tsp bs eggs, and 1 ltr water in the bottle
  5. Put in the airline and turn on the pump
  6. Wait 24 hours
  7. Turn off the air and check to see if the eggs have hatched, if not wait another 6 hours approx
  8. Once the eggs have hatched leave it standing for about 10 minutes for the egg shells to float to the top
  9. If you shine a light at the bottle the brine shrimp will congregate there
  10. use airline to siphon out the bs and strain it through two layers of a hanky