The Question
I remember going to my first convention. It was the first time I had seen customers face-to-face. I was amazed by how many people were there, and eager to answer all of their questions. The grand display tank was filled with large moon jellyfish pulsing around the tank. People adored them. I adored talking to them. As I talked to them, I noticed a pattern. Many of the same questions came up, time and time again. One of the most prominent ones was this:
“But… What do they eat?”
Answering this question, again and again, I just knew I had to write this blog.
The Wild Truth
Well, first things first, all jellyfish are predators. But jellyfish aren’t just any predator, they’re lazy predators. They’re completely opportunistic. They eat whatever happens to drift by and become entangled with their tentacles. They then they use their oral arms to take the captured prey from their tentacles up to the very center of their bell, and into their (very tiny) mouth. Incidentally, this mouth also happens to be their anus. They’re rather fortunate that they don’t have taste buds.
In the wild, most jellyfish feed on plankton, which is made up of thousands of microscopic species of swimming animals. Jellyfish only eat zooplankton (animals that eat plants or other animals), not phytoplankton (plants that produce their own energy from the sun). Some species of jellyfish, such as the Upside Down Jelly, host symbiotic algae within their oral arms. This algae provides extra nutrition to the jellyfish by producing organic material through photosynthesis. Many species of jellyfish feed on other species of jellyfish. For example, the Sea Nettles feed on Moon Jellyfish.
Jellyfish can also be fed live food, such as baby brine shrimp. This food is highly nutritious and recommended especially for sick or struggling jellyfish. Public aquariums have a full time staff, so they almost always hatch their own baby brine shrimp daily to feed to jellyfish. Depending on the species of jellyfish, sometimes public aquariums also feed the jellyfish rotifers, blended krill, chopped fish, and other foods. Public aquariums rely on these time-consuming foods because they often keep exotic species, breed jellyfish and run experiments.
However, hobbyists can use Jellyfish our dry and live food to suit their jellyfish’s needs.
But What Do I Feed Them?
We provide a dry jellyfish food specifically formulated for jellyfish made from plankton high in HUFAs (Highly Unsaturated Fatty Acids), which are essential for proper nutrition. We strongly suggest only feeding jellyfish with our recommended food.
Other fish foods that claim to be suitable for jellyfish are often low quality. Follow the feeding guide to properly feed your jellyfish with special care not to overfeed which can cause water quality issues.
Our high quality Jelly Food includes a small scoop included inside the food bag! For 3-4 jellyfish feed 1/4 scoop of dry Jelly Food in total once per day. Feeding amounts may be adjusted gauging that minimal food is left on the aquarium floor.
During feeding you should mix the dry food in a small container with a small amount of aquarium water, this solution can be dispersed into the aquarium.
Using a container of any sort (I often use a neglected egg cup), I fill it with a bit of water from my jellyfish aquarium using a baster. I wouldn’t take out more than a cup of water from your aquarium for this procedure, as that’s just unnecessary. Then, I pour in a measured amount of dry food into the container of tank water (there is a spoon included in our food packages to do this). I personally just use the spoon itself to mix the food and the tank water, and then leave it. Take this time to thoroughly dry off the measuring spoon if you’ve used it to mix the water. Let the food sit a bit in the water for some time. Not too much to float, and not to much to sink. That’s what you’re looking for.
Once my dried jellyfish food has been prepared, I slowly squirt the food back into the tank with the baster, making certain to avoid any bubbles in the water. Contrary to popular belief, it is best to avoid squirting the food directly at the jellyfish. Instead, squirt the food into the current so that the jellyfish can exercise their tentacles and oral arms. And now, watch. The food should be slowly drifting into the water current. Some will go through the vents, but the filter sponge will take care of that. The majority of the food should be flowing through the current in the tank, allowing the jellyfish to catch it in their tentacles. As time goes on, you may start to notice your jellyfish’s stomach slowly turning a brownish colour as it is filled with food!
Though the jellyfish are not very active, watching the jellyfish feed is a soothing activity. Just be certain not to overfeed your jellyfish! This will cause your water to get polluted by the uneaten food that will rest on the bottom of the tank. Your jellyfish will be unable to eat this, as it is not in the water current. If you have fed your jellyfish too much, simply siphon out the excess from the bottom of the tank.
But Is Dry Food Enough
Ah, the question I’ve been waiting for! Is the freeze-dried zooplankton enough? Simply put, no. Not on its own. It does need supplementing. We have thought over this, and has taken action to provide the proper supplementation to our dry food. The supplement? Brine shrimp.
The reason that we don’t just use frozen brine shrimp is because it simply isn’t as nutritious as live. In addition, though frozen brine shrimp is readily available, it’s often the wrong size for jellyfish. Jellyfish have small mouths, and the frozen brine shrimp on the market is often too large for the jellyfish to eat. What jellyfish need are freshly hatched brine shrimp.
To hatch brine shrimp is simple. To make it simpler, we provide the Brine Shrimp Hatchery Disk, which makes hatching brine shrimp easier than ever before. Simply put diluted salt water into the disk, a spoon full of eggs, and place the hatchery disk in a warm area. The brine shrimp will hatch within the next 12-24 hours, and you will have live, freshly hatched brine shrimp ready to feed your jellyfish with!
The process of feeding the brine shrimp is much the same as with feeding live food. Using a baster, transfer the amount you need from a container of tank water and brine shrimp, and slowly push the brine shrimp into the current.
Feeding live food to your jellyfish helps them live longer, look better, and keeps them more active. In addition to being much healthier for your jellyfish, it also means there’s less mess to clean up, as the brine shrimp stay in the current longer for the jellyfish to catch them. For these reasons, at Jellyfish Aquarium, we like to feed freshly hatched brine shrimp more often than dried food.
Of course, this does not discount the dried food. Often, it’s best to use a bit of both to give your jellyfish the best lives possible. And not matter what food you use, your jellyfish still poop. So you will still need to do weekly maintenance on your aquarium.
Bon Appetit
Today we covered what jellyfish eat in the wild, what we feed them in captivity, how to feed them and how often to feed them. It’s a food for thought when purchasing your jellyfish supplies, but maybe you’re still looking for dessert? In which case, below is linked a variety of sources on what jellyfish eat, and how they eat. If you’re interested in learning more about brine shrimp, feel free to reach out an email us through our contact page, or wait for us to post a blog all about brine shrimp, and how to make your very own brine shrimp hatchery!
Best of luck with your jellyfish, and don’t forget to check in next week for more news on the Jelly Roll!
Next Blog: To Care for Jellyfish
If you want more jellyfish content, a certain topic addressed, or you saw a really cool article on jellyfish, please tell us your thoughts in the comments below!
Purchase Jellyfish Food!
Jellyfish Food: https://jellyfishaquarium.ca/product-category/jellyfish-supplies
Brine Shrimp Hatchery: https://jellyfishaquarium.ca/product/brine-shrimp-hatchery-dish
Sources:
What Jellyfish Eat-
- http://www.whatdojellyfisheat.info
- https://animalinfoworld.com/what-do-jellyfish-eat/
- https://animalsake.com/what-do-jellyfish-eat
- http://www.whatdojellyfisheat.info
How Jellyfish Eat-