A frequently asked question from people who just started their first-ever brine shrimp tank is this:
When should I start feeding the babies after they hatch?
“Feed them as soon as they hatch!” would be my advice.
This approach may differ from the official guideline from Sea-Monkeys or Aqua Dragons, but it has worked for all my hatching attempts. It is also based on the following reasons.
1.
First of all, let’s consider the basic biology of brine shrimps.
– Newly hatched babies have yolk reserve that they rely on and don’t need feeding. Theoretically, this reserve can last them for up to 5 days*. HOWEVER,
– Within a day (or more precisely, 12 hours**) after hatched, the babies would have developed digestive tract and can start feeding.
In the natural habit, the eggs would be hatching in water teeming with microscopic algae. Those algae are the primary food source for brine shrimps. As there are no barriers between the babies and the algae, hatchings will start feeding as soon as they can.
The reserve can last for a few days, yes, but that is more of a backup for the rainy days. As with the natural environment, the condition may fluctuate, so it is good to have some reserve as a survival strategy. They will feed as soon as they are able, though. And that is within a day after they hatch.
2.
The second thing to consider is if there is already food for brine shrimps in your hatching solution.
If you homemade everything from scratch, hopefully you already know what you put in there….
If you use an aquarium-hobby-oriented salt product specifically for hatching brine shrimps (Artemia), some are formulated with food in the mix already. This would be stated on the label with more details in the instruction.
If you use toy kits such as Sea-Monkeys or Aqua Dragons, it is complicated. Because those companies tend to regard their mixes as trade secrets, they don’t usually reveal the exact ingredients. Unless you have a microscope and possess the know-how to inspect and identify matters under the lens, it is hard to say what is there.
Their formula can be changed from time to time as well. For example, I was trying to hatch both the standard Aqua Dragons and their “In Space” version at the same time. When I dissolved the egg/salt premix, I noticed that the standard AD mix contains a small but noticeable amount of tiny green flakes that do not dissolve, which are likely to be algae powder food. The In-Space version, however, did not contain similar green powder.
As it is impossible to guess what each company has put in each of their product, I would always advise people to start giving food as soon as the babies hatch.
3.
The final thing to consider is the human factor.
How we interpret when hatching happens are pretty subjective, especially for people who keep it as pets and not really measuring it like a science project.
Newly hatch babies are so tiny and translucent that many people may not notice that they are actually there until a bit later. (The baby could have gone through developmental stages and grow into a larger form within a day or two.)
And unless you are watching the tank 24/7, they may have hatched early in the night, and then 8 hours would have passed when you saw them in the morning.
Therefore, by the time when people think the babies are hatching, it could have been a day from when it actually happened.
That is another reason why I think food should just be given as soon people see that the babies have hatched.
So, if you have been through the situation where the babies hatched, you followed the kit instruction and waited for a few days to feed them, but they were already dead before that…. Next time, just try feeding them as soon as they hatch and see if that makes a difference.
* ** Reference
Recent Developments On The Application Of Artemia In The Ornamental Fish Culture
Page 648
“Approximately 12 hours after hatch it molts into the second larval stage (Instar II) and starts filter feeding on microalgae, bacteria and detritus. The Artemia nauplius can live on yolk and stored re-serves for up to 5 days or through the Instar V stage (Fig. 3), but its caloric and protein content diminish during this time (Briksi et.al., 2008). “
Page 2
“At hatching, the nauplius larva (= instar #1) emerges as a free-swimming stage (Figure 1H)…. The nauplius larva does not have a complete digestive tract and does not immediately feed. It relies on stored yolk as an energy source. Depending on temperature, it swims weakly for about 12-20 hrs and then molts into the metanauplius larva (= second instar). The metanauplius larva is translucent in color and about 0.6 mm in length (Figure 1I). Its trunk region is noticeably longer, and this region continues to lengthen and differentiate through the next series of molts. The metanauplius swims vigorously using its second antennae which are now better developed. At this stage, it starts filter-feeding. Its food consists mainly of microalgae,
bacteria, and detritus.”
