What Do Sea Anemones Eat?

Members of the sea anemone genus are often thought of as plants due to their flower-like appearance, but this underwater invertebrate is, in fact, an animal. As such, they need a hearty diet to survive. All sea anemone species are carnivorous, relying on a variety of proteins to survive and thrive.

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These wild and beautiful creatures can make a great addition to your aquarium but need to be taken care of with a healthy diet that meets their nutrient needs, and in a clean space where they can thrive. Most sea anemone types tend to consume small fish and crabs, though some larger breeds have even been seen eating birds and ants. Having a good balance of protein in their diet is important to help them grow. The more they eat, the more "legs" they gain, which increases their size and strength.

There are more than 1,000 species in the sea anemone genus. Certain sea anemone types, including pink tip, saddle carpet, bubble tip, mini carpet, and rock flower do better in a home aquarium than others and can be easier to care for. But regardless of the species, they all require certain specifications and diet to survive, including water temperature, nutrient levels, and lighting.

Some sea anemone species are able to move around. If they don't like the spot you choose for them in the tank, they might relocate elsewhere until they are content. Movement can be a sign that water conditions need to be improved.

As obligate carnivores, most sea anemone species seek out foods filled with protein. Since they live underwater, this usually means small sea creatures. They typically seek out tiny fish or plankton. The sea anemone and clownfish have a symbiotic relationship. Living within its tentacles, the waste of the clownfish provides fuel and nutrients.

The larger the sea anemone, the larger the food they seek, though it's still on the small side. More petite anemones consume almost microscopic-sized fish, while bigger ones have been known to eat beings as big as jellyfish and crabs. It was recently discovered that some large sea anemones eat ants, though they mainly consume things that are part of their own ecosystem.

Some smaller sea anemones rake their food in, but most capture it. Using their stinging cell tentacles, called nematocysts, wild sea anemones shock their prey with their venom. This paralyzes their prey so it can't move or escape.

These barbed, stinging tentacles also help them grab potential food as it is traveling by, reaching out to catch it. The sea anemone then feeds itself with its tentacle, using it as a hand to put it in its mouth, which opens to indicate hunger. Anemones have stomach acid that breaks down protein into an easy-to-consume liquid, and they spit back out anything inedible to them.

Protein is important to a sea anemone's energy levels and daily function. When keeping a sea anemone in your fish tank, they consume a bit of algae but need to eat meat a few times per week. For some, it can help them grow larger, even increasing the number of tentacles they have.

Unlike other beings, there is no limit to the number of limbs sea anemones can grow. Like plants, they can continue to grow more body parts throughout their entire life. Though the process is not the same as regeneration done by other animals who make more limbs due to getting hurt or sick, many species, like the starlet sea anemone, repeatedly make more arms based on the amount of food they consume.