Brine shrimp is a popular fry food, but if you allow the brine shrimp to grow a bit bigger it will actually serve as a great food source for a lot of adult fish. By cultivating your own live food you can ensure that it is disease free, thereby greatly reducing the risk of getting outbreaks of ill health in your aquarium.
What you need:
One small glass tank (the hatching tank)
One bigger glass tank (the growing tank)
One sheet of rigid plastic
One small stainless steel self tapping screw
Dedicated air supply for both tanks, e.g. airstones
One bag of sea salt
Brine shrimp eggs
A flashlight or similar source of light
If you want your brine shrimp to grow really big, you can set up a third tank to provide the growing specimens with more room.
How to go about:
- Divide the tank into two parts, one part being 2/3 or the tank. You can for instance use rigid plastic as a divider. Cut a 1 ½ inch hole in the centre of the divider. This whole will allow the shrimp to swim through. Do not attach the divider yet, because you will be doing some work on it.
- Black out the 2/3 part of the tank, including the lid. Your aim is to create a dark area inside the tank, while leaving 1/3 of the tank non-dark.
- Cut a disc of plastic big enough to cover the hole in the divider.
- Drill a small hole in the disc, and another in the divider. The idea is to make the small piece act as an eyehole and when swung into position it will cover the entire hole and prevent any light from entering the blackened part of the tank.
- Now is time to attach the divider and make sure that it fits snuggly.
- Calculate how big your tank is and create strong enough saltwater in your tank according to the instructions on the sea salt bag. The salinity should be somewhat stronger than for marine fish. Only use dechlorinated water since chlorine and chloramines can harm the brine shrimps.
- Put the partition in place and make sure that the blackened part of the aquarium is really dark.
- If the room where you keep your brine shrimp hatchery is cold, install a heater that will keep the water temperature around 65-70 degrees F.
- Install and turn on the airstone in the dark side of the tank.
- Add no more than a quarter of a teaspoon of brine shrimp eggs to the dark side.
- Make sure that the airstone is potent enough to prevent the eggs from settling on the bottom.
- Cover the tank and leave the eggs in complete darkness for 36 hours before you check for shrimp. The eggs will normally hatch after 36-48 hours. .
- Set up the big, growing tank and fill it with saltwater (the same salinity as in the hatchery tank). This tank should not be blackened or have any divider. Placing it near a window is actually recommended, since the light will be beneficial. Install an airstone to ensure water movement. If the room is cold, install a heater that will keep the water temperature around 65-70 degrees F.
- As soon as the brine shrimps have hatched, turn the airstone off in the hatching tank for a while and wait for the eggs to settle. (Do not forget to turn it back on later!)
- Once the eggs have settled, open the eyehole. (Please not that the dark part must be kept dark at all times).
- Place your flashlight near the light side of the tank and wait for the shrimps to swim through the hole. They will be attracted by the light. This method will fill the light side of your tank with live shrimp, while shells, unfertilized eggs and dead shrimps will stay in the darkened part.
- Use a siphon to remove the shrimps, net them and place them in the big growing tank. (A part of the batch can of course be used to feed your fish directly.)
- Every time your remove eggs, shells and dead shrimp from the dark part of the hatchery tank, you should add some new eggs to keep the hatchery going.
Feeding the brine shrimp
To make your brine shrimp survive and grow really big, you must provide them with suitable food. In seawater, there is always an abundance of tiny food particles for newly hatched brine shrimp to feed on, but since we use tap water + salt we have to add food. (If you want to, you can of course collect seawater and use it for your hatchery and growing tank, provided that you can obtain fairly non-polluted seawater.)
During the first few days after moving your brine shrimp to the growing tank, feed them 1-2 drops of liquid fry food per day. Overfeeding is dangerous since it will pollute the water.
One the brine shrimps have reached a size of roughly ½ mm you can start giving them egg-yolk paste. (See recipe below.) Dip a match into the tank, then 1/8 inch into the egg-yolk mixture, and then back into the tank. It might seem like an immensely small amount of food, but it will be enough. Feed your brine shrimps no more than twice a day, ideally while it is still light. As they grow bigger, you may be able to increase the amount of food slightly without fouling the water. If you have placed the growing tank close to a window there will also be plenty of algae for the brine shrimp to feed on.
Egg yolk paste recipe
- Hard boil an egg and discard the egg white.
- Mix the egg yolk with one tablespoon of Bemax (or any other similar health food product, the important thing is to use a non-flavored variant). If you cannot obtain health food, try dry baby food. The result should be a smooth paste.
- Mix in a few drops of liquid fry food.
- Mix in a pinch of flake food.
- Shape the paste into really thin biscuits on top of a baking tray.
- Cook in the oven under low heat. The aim is to make the biscuits dry, not to really cook or burn them.
- Remove from oven and leave to cool.
- Use a rolling pin to crush the biscuits into a really fine powder. The smaller the particles, the easier for your brine shrimp to eat them.
- Store your brine shrimp food in a dark, airtight container.