Decapsulating Brine Shrimp Eggs

Baby Brine Shrimp are one of the most popular food for killie fry but hatching the eggs can be troublesome. Quite often, hatch rates are poor if the eggs are of poor quality or if they were not kept in proper conditions. Gwee Sia Meng, a good friend and killifish enthusiast has a solution to this problem. He removes the outer shells of the brine shrimp eggs before hatching them, a process known as decapsulation. Here's how Sia Meng does it.


The items needed to decapsulate brine shrimp eggs are bleach, vinegar, a coffee filter, a plastic cup and of course, the brine shrimp eggs themselves. Duh.
Sia Meng fills up a brine shrimp hatchery bottle with about one litre of tap water. He then pours into the water one film cannister of brine shrimp eggs.
The solution is hooked up to an air pump and aerated for about one hour. This is to rehydrate the eggs so that their shells become soft.
A cup of bleach is prepared. Bleach, by the way, is more commonly known as Chlorox in Singapore. Ask your wife, girlfriend or mother if you don't know what's Chlorox.
The bleach is poured into the hatchery bottle and the solution continues to be aerated. It's important to watch the colour of the eggs closely now as it will change when the shells are dissolved by the bleach.
The eggs are brown before the bleach is added.

After about 10 minutes, the eggs turn orange in colour. This signals that the shells have been dissolved.

The air pump is switched off and disconnected from the bottle.

The solution is poured through a coffee filter. Do not use coffee filters made of cloth as the eggs will stick to the sides. Use only plastic coffee filters.
The eggs are washed with running water. Sia Meng stirs the solution with a chopstick and washes the solution until there's only a faint smell of bleach. It's impossible to get rid of the bleach completely at this stage so don't even bother to try.
The coffee filter holding the eggs is placed into a jar filled with some water.
A cup of vinegar is prepared.
The cup of vinegar is poured into the coffee filter.
The solution is stirred for about 5 minutes. This will remove the bleach completely as vinegar neutralises bleach.
The coffee filter is positioned under a tap and washed with running water to get rid of the vinegar.

Look Ma, No Shells!!

This is how the eggs should look like at this stage.

One table spoon of marine salt is added to a small plastic container to prepare a super-concentrated salt solution.
The solution is stirred to dissolve the salt. Don't worry if the solution becomes saturated and some salt cannot be dissolved. The idea is to make it as "salty" as possible.
The decapsulated brine shrimp eggs are transferred into the salt solution.

Unlike normal brine shrimp eggs that float, decapsulated brine shrimp eggs sink. This is because the shells are no more so they are not as bouyant. Keeping the eggs in a salt solution is to dehydrate them. The salt solution, through osmosis, will extract the water from inside the eggs.

The container is kept in a fridge (vegetable compartment) and whenever he needs to hatch some, Sia Meng uses an eyedropper to extract the eggs.

To hatch decapsulated brine shrimp eggs, the process is similar to hatching the normal ones with shells. The hatching period, however, is shorter and it takes only about 16 hours for decapsulated eggs to hatch as opposed to about 30 hours for normal eggs.

Baby brine shrimp tend to congregate at the bottom of the solution after they are hatched. You can see from the picture what a good hatch rate Sia Meng got from using decapsulated eggs.

Besides getting better hatch rates, other good reasons for decapsulating eggs are:

1. Even unhatched eggs can be eaten so nothing is wasted.

2. Baby brine shrimp hatched from decapsulated eggs are more nutritious as less energy is used for hatching.

3. No more egg shells floating on the water surfaces of the fish tanks.