What Do Lionfish eat?
Let’s discuss feeding your lions. First of all, let’s talk about live feeder fish. The flesh of freshwater fish does not contain the proper fatty acids required to keep saltwater predators healthy. This is especially true of members of the carp family, such as goldfish, koi, and rosy reds. Another big problem is that these fish also contain high concentrations of the enzyme Thiaminase, which inhibits the uptake of Thiamine. An extended diet of freshwater feeders usually results in poor growth rate, disorders of the nervous system, clamped fins, cessation of feeding, and you guessed it, an early death.
Another food to avoid is krill, frozen or freeze-dried. Krill has been linked to lockjaw in many predatory species, and although it is typically well-received by most fish, it is not recommended. In fact, some people in the hobby refer to freeze-dried krill as fish crack since some fish will decide they will only eat this food and nothing else once it has been offered a few times.
About now is where you might be wondering “OK, smart guy, just what DO I feed my fish?” so let’s find out:
What Do I Actually Feed My Lionfish?
While we don’t recommend a steady diet of live food, it may be necessary to feed newly acquired specimens live fare initially to get them eating, or in some cases, where certain fish are difficult, or simply refuse to be weaned onto dead foods, this may be their diet for life.
Ghost or grass shrimp (fresh or saltwater) are both excellent foods, especially since they can be enriched (gutloaded) with nutritious goodies like high quality flake food, spirulina, beta glucan, etc. simply by feeding your feeders a last supper or two of nutrition-packed goodies.
Livebearers, such as guppies, mollies, or platies are also good choices. These fish can also be enriched prior to feeding them out. You may want to go the extra mile and convert them to brackish or full saltwater if this will be a long-term feeding option.
Appropriately-sized damsels make great feeders, and can sometimes be ordered in lots at a discount at some LFS or e-tailers. We usually give these fish a 20-minute freshwater dip prior to feeding them out to decrease the risk of introducing parasites.
Live saltwater minnows or anchovies also make tasty treats, so if you have access to them, and can find them of appropriate size, they are a good alternative if live foods are necessary. Be careful of collecting them off of wharfs or piers, as the water in these areas are often tainted with pollutants.
We would like to note that smaller specimens will also hunt down live pods with great relish and will decimate a tank’s population in fairly short order.
Silversides are an excellent food since they are easily stuffed with pelletized food, powders such as spirulina, vitamins (C, B6, B12) or beta glucan, etc. One can also find many other frozen foods in the freezer at the local fish store (LFS), however, I find that a wider variety of fresher, high quality seafood is available at the grocery store or local fish market. Surprisingly, when purchased in small amounts, it is actually less expensive to feed your lions people-food rather than fish food. Some of the foods we’ve had good success with are red snapper, salmon, tuna, cod, shrimp (uncooked, shell-on), lobster, scallops, clams, and squid. Try what’s on sale, try different foods to see what your fish find tasty. These foods can be cut up into bite-sized chunks, placed into bags and frozen for later use. If you arrange individual feeding bags, it is easy for a fish sitter to feed the fish should you be out of town for more than a few days for some reason.
Smaller specimens will also take mysis (we use Hikari and Piscene Energetics), and even brine shrimp (we use Hikari Brine Shrimp Plus). With the exception of one of our stingfish which eats PE mysis from a pile on the substrate, these foods are simply thawed, rinsed, and placed into the water column.
We’re often asked “how large should the chunks be?”, and although it depends on the size and species of the fish and its mouth size, if you stay right around the size of the fish’s eye or just a tad larger, you’ll never be wrong. If your fish happens to get a larger chunk than you had planned and seems to be choking, what the fish is actually doing is repositioning and softening the food item prior to swallowing. If this happens a lot, try giving the fish smaller chunks.
Due to their sedentary nature and slow metabolism, adult lionfish should only be fed twice or three times a week. Feed them until you see a slight bulge in their bellies, once you see this, you will understand my meaning. We do, however, feed our juvenile specimens a bit more often since much of their caloric intake is used for growing. A good feeding schedule for us has been to feed the adults Monday-Wednesday-Friday. Our juvies typically get a bit of food each day between normal feedings.
Given the chance, many lions will overeat, sometimes to the point of regurgitation, which obviously, should not be encouraged. In a short time, you will get a feel for how many food items of appropriate size make up a meal for your fish.
Overfeeding your fish on a long term basis will likely shorten its life due to hepatic lipidosis (fatty liver degeneration). Additionally, owing to these fishes’ slow metabolism, large food items can sometimes begin to decompose in a lionfish’s digestive tract before it can be digested, resulting in bloating and death. Don’t worry if this paragraph seems scary, it’s simply helpful to know.