I started hatching brine shrimp eggs around two months ago when my molly fish (a live-bearer) was about to give birth. I had read the Brine Shrimp FAQ (available at http://www.users.interport.net/~spiff/resourcestxt/brineshrimp.html) and found it to be useful background and technical information. But while they referred to commercially available brine shrimp hatcheries or shrimpolators, I could not find such boxes or devices sold in our local fish shops. So I devised my own with some initial advice from Mr Jeremy Lee (firstname.lastname@example.org). The following is my method of hatching brine shrimp eggs for successful feeding of my molly fry. I have now two batches of fry, one batch of 40+ about seven weeks old, and another batch of 45 fry just three weeks old. They are indeed a bunch of happy bellies.
WHAT YOU NEEDA. Brine shrimp eggs. I bought O.S.I. (Ocean Star International) brand brine shrimp eggs at $8.50 for a 26 gm bottle, from a fish shop in Bedok. (They have a smaller bottle costing $5.50 for 9 gm). It comes with a double ended plastic spoon, the larger end of 5 ml for scooping and measuring the salt, and the smaller end of 2.5 ml for measuring the amount of brine shrimp eggs to use in hatching. [Note: The shop in Bedok has since stopped selling brine shrimp eggs. Another good source is Lam Hong Aquarium, Blk 163 Ang Mo Kio Ave 4 #01-476, Tel : 6452-5780] B. Sea salt. I buy sea salt from the fish shop at 50 cents for a small packet, or $1.50 for a large packet. You can also use aquarium salt, but it costs more. If you want to use table salt, make sure that it is free of iodine. C. A hydrometer to measure the specific gravity of the salt solution for hatching the brine shrimp eggs. I bought a combination hydrometer/thermometer (long glass object which floats vertically in water as it measures) costing $8.50. D. Two empty 1.5 litres plastic soft drink bottles with the top 8 cm (including the cap) cut off. Those with clear plastic are preferred so that you can see through the bottle to check on the brine shrimps. E. Optional: A half-height narrow plastic basket to contain the two bottles to help prevent them from toppling over. Spilt salt solution and brine shrimps can be sticky and messy. F. Aeration for the two brine shrimp cultures. Your existing air-pump might do. My old one was not powerful enough to support so many air points, so I bought a new air-pump costing $18. It has two air outlets and high-medium-low switch. Even at low setting, it can support up to 8 air points of varying air pressure with the help of gang valves. Keep those valves higher than the tank water or brine shrimp culture so that when the air is stopped, there can be no back-flow of salt water into the valves. Also miscellaneous items like two short air tubes with lead strips (from your aquatic plants, or you can buy them in long strips from your fish shop and cut to size) attached at one end to weigh them down in the brine shrimp culture for aeration purpose. G. A very fine net to sieve the brine shrimps before feeding to the fry. Cost: about 80 cents. H. Optional: A turkey baster (over-sized plastic syringe with rubber pump at one end) for mixing the salt water and sucking out the brine shrimps later on. You are unlikely to find the baster in the fish shop, but you might want to try the household goods section in the supermarket. The cost of a turkey baster should be around $3. If you do not use a baster, then you may have to use your mouth to suck the brine shrimp with the help of an air tube and run the risk of having a mouthful of brine shrimp. I. Yeast to feed your brine shrimp. The instant yeast sold at your local supermarket or bakery supply shop will do fine.
STEP-BY-STEP GUIDE TO BRINE SHRIMP CULTURE1. Start with one bottle first. Make sure that it is washed thoroughly to get rid of the smell and taste of soft drinks. You may use a diluted Clorox solution to disinfect it, but be sure to rinse off the Clorox and do not allow any Clorox to drop into your brine shrimp culture or fish tank. 2. Pour stored water into the bottle until it is about 2 cm below the rim. The water should have been stored and aerated for at least a day to get rid of the chlorine. This amount of water should yield a brine shrimp culture of about 1.2 litres. 3. Put the combination hydrometer/thermometer into the water, and put about two and a half spoons full (the 5 ml size spoon) of sea salt into the water. At this stage, I use the baster to pump the solution, taking care not to spill it. You can hear the salt crystals swishing about at the bottom of the bottle as it is agitated and dissolved. Check the hydrometer to see whether the mark 1.020 on it (usually marked with a green line) is level with the salt solution. If not enough, add some more salt a little at a time, and mix again with the baster until the measurement is correct. If you do not have a baster, you can use your air tube to aerate the solution but this method will take a longer time, and can get quite messy, as the bubbles from the strong aeration burst and you may find a white coating of salt and brine on your nearby tank, etc. I prefer to use an air tube weighed down by a strip of lead around one end, rather than an air-stone, as the latter clogs easily in the salt solution, and also the fine bubbles from the air-stone are more likely to leave a layer of salt dust and brine on the nearby tank and other objects. 4. After the salt solution is of the required salinity, remove both the air tube and hydrometer from the culture bottle, and put them temporarily into your fish tank. Then measure and put one-half or slightly more than half spoon (the 2.5 ml spoon) of brine shrimp eggs into the solution. The reason for taking out the hydrometer and air-tube temporarily is that brine shrimp eggs are very light, and will stick to objects as well as to the side of the bottle if the water is agitated while the brine shrimp eggs are poured into it. By putting the eggs into a completely still solution for about half to one hour, a lot of the eggs will become wet by themselves, and sink into the solution. This will give a higher yield of brine shrimps. After half an hour or so, put back the hydrometer and air-tube into the brine shrimp solution, and turn on the air to bubble slowly. Most of the eggs will begin to sink into the water. 5. The brine shrimps will start hatching in about 24 hours. You should wait a few more hours if you observe that the nauplii (newly hatched brine shrimps) are still attached to their egg shells as the shells are not palatable to the fish fry and may cause digestive problems if eaten by the fry. 6. Once the nauplii are ready for feeding to the fish fry, shut off the air supply to the brine shrimp culture. Wait about 15 minutes for the brine shrimp solution to settle. The empty egg cases will float to the top, while the unhatched eggs will settle at the bottom of the solution. Get ready your baster and fine brine shrimp net and an empty plastic container, to harvest the brine shrimps. You may also want to shine a bright light or flashlight at the side of the brine shrimp culture in order to attract and concentrate them in one location for easier harvesting. 7. When you are ready to feed the fish fry, shut off the air supply to the filter in the fry's tank (to prevent the brine shrimp from being sucked into the filter). To harvest the brine shrimp with the baster, squeeze out the air from the baster first before dipping it into the solution, aim the tip of the baster in the middle of the solution where the brine shrimps concentrate, and slowly suck in the brine shrimp before lifting out the baster, and straining the brine shrimps into the fine net over the empty plastic container. You can see the reddish colour of the tiny brine shrimps in the fine net. Depending on the number of fry that you have to feed, you may want to repeat the harvest a second or third time, taking care not to agitate and mix up the solution in the brine shrimp culture. If you do not have a baster, then you might want to use a length of air-tubing to siphon out the brine shrimp from the culture into the fine net over an empty plastic container. With this method, you have to be quick so as not to get a mouthful of brine shrimp when you suck to start the siphon, as well as to stop the harvest when sufficient brine shrimp has been siphoned out. 8. The fine net with the strained brine shrimp may be washed gently with tap water in order to make the brine shrimp less salty, taking care not to wash away the brine shrimp, before it is used for feeding the fish fry. I do not bother to wash away the saltiness of the brine shrimp when feeding my molly fry as a little salt does them no harm. After about 10 - 15 minutes when the fry has consumed the brine shrimps, you should not forget to turn on the air supply to the filter. A watch with a timer function is useful as a reminder. 9. In the meantime, the salt solution collected in the empty container may be poured back into the brine shrimp culture if there is still a lot of brine shrimps left in it, or it can be discarded (not into your flower pots or plants or tank as it is salt water) if the density of the brine shrimp is visibly less. In the latter case, as the brine shrimp solution is drained down with each feeding, you should plan to start the second culture of brine shrimp in the other bottle, bearing in mind that it takes about 24 hours for a new batch of brine shrimp to hatch. When the culture in use is almost finished, wash out the contents thoroughly with clean water, making it ready to start a new culture when needed. 10. If each bottle of your brine shrimp culture can last a few days, you might want to feed your brine shrimp. Make a yeast solution in a small bottle by mixing some yeast with a little water from your fish tank. When the solution is milky, use the baster to feed a few drops into the brine shrimp culture, and store the bottle of yeast solution as well as the unused yeast in another small bottle in the refrigerator. Do not put the yeast powder directly into the brine shrimp culture, as this is likely to lead to overfeeding of the brine shrimp, and making the solution cloudy. Brine shrimps are filter feeders, so it is not necessary to have strong aeration in the brine shrimp culture, or else they will spend too much energy struggling against the current. 11. It is not necessary nor desirable to feed your fish fry exclusively on brine shrimps. After a few days, you should start introducing flakes to your fish fry, and this can be supplemented with shrimp pellets as the fry gets older. Brine shrimp is salty, and fish fry may not grow well if fed exclusively on brine shrimp. 12. It is economical to feed fish fry with brine shrimps, as a bottle of brine shrimp eggs can be used to hatch countless batches of brine shrimps. Brine shrimps provide a good source of food for fish fry, as the fry are more likely to get equal share of the brine shrimps during feeding time, resulting in uniform growth of the fry. Furthermore unlike other forms of live food such as tubifex worms, brine shrimps are not known to contain pathogens or contaminants which can endanger the health of your fish.
Click here to return to Teo Soon Bock's Home Page.