Keeping a Lobster as a Pet: A Short Care Guide

People keep all kinds of aquatic animals in their tanks, even though some can seem a bit weird as pets. Youtuber Brady Bradwood rescued Leon the lobster from a grocery store and put him in an aquarium. Does this sound crazy? Maybe, just a little bit. Can lobsters survive in a tank? Definitely, yes, under the right conditions.

What is a lobster?

Lobsters are uncommon in the aquarium hobby, even though they are fascinating marine creatures. They are naturally benthic crustaceans dwelling on the bottom of the sea. They usually go foraging for food and groom a lot during the night. However, as they get more comfortable with their surroundings, they may begin to wander around during the daytime too.

These crustaceans like cold and salty ocean waters and usually hide in rocks and weeds.

Lobsters come in many colors and sizes.

Most species have two large claws in the front.

They have a hard shell called an exoskeleton. They need this exoskeleton to hold their shape and protect them, as they don’t have bones in their bodies as we vertebrates do.

This shell or crust leads to their group name – crustaceans, which include shrimp, krill, and barnacles.

How big does a lobster get?

Most lobsters grow between 9.8 – 19.7 inches long and, weigh up to 15 pounds, and usually live between 40 – 50 years.

Most lobsters are harvested when measuring between 3 ½ and 4 inches long, and lobstermen in the US are legally required to release lobsters larger than 5 pounds to allow them to reproduce further.

The record weight for a lobster was 44 pounds and 6 ounces. It was an American lobster (also called Maine lobster) caught in Nova Scotia in 1977. There have been lobsters known to have reached 100 years.

Usually, to find out a lobster’s age, you should multiply its weight in pounds by 4, and add 3 years. In the USA, Lobsters can legally be harvested at about 7 years old, usually reaching about 1 pound.

What color is a lobster?

Although most people know lobsters to be red, be aware that they only turn red when cooked. Most lobsters are a greenish-brown color, with some of them being of a blue shade. Some can be white, yellow, or multicolored.

What do lobsters eat?

In their natural habitat, lobsters feed on fresh food like sea urchins, shrimp, clams, mussels, mollusks, worms, crabs, starfish, and other small fish or shellfish. Watching a lobster open a clam to get to the meat inside is fascinating.

Make sure you choose foods that can sink to the tank bottom in a tank. Lobsters don’t swim to the top, so they won’t eat anything from the water’s surface. Floating foods may be suitable for its tank mates, though.

Cannibalism

Lobsters are territorial. They may get cannibalistic and eat other lobsters in rare circumstances. In the wild, lobsters can avoid each other, which doesn’t happen in grocery stores.

In grocery aquariums, lobsters are not fed to keep the water clean and avoid poop. As a result, they become starving and resort to cannibalism to survive. These aquariums are small and overcrowded, resulting in very stressed lobsters that may fight and kill each other. That is why they put rubber bands around their claws.

Gastric Mill

They do have teeth – although not in their mouth. The lobster’s teeth are located in its stomach and are called the gastric mill.

Feeding

In a tank, you can feed your lobster pellet food that sinks to the bottom of the tank. Only provide as much as it can eat in a few minutes, once or twice a day, to prevent food decay, which contaminates the water.

Apart from pellets, you can also feed it frozen brine shrimp, tubifex worms, and bloodworms. If you keep other fish, ensure they don’t eat all the food before reaching the lobster. Killifish especially may charge at the delivered food, preventing the lobster from eating anything.

Lobsters like to munch on seaweed and algae for some extra vitamins. It would help if you had a few hours of sunlight each day for seaweed and algae. Your crustacean will thank you for it!

How do lobsters reproduce?

Lobsters reproduce through eggs. A female will shed her shell, called molting, inside a male’s cave, mate with him and spend her first days with him. After the male fertilizes them, the female will carry the eggs under her tail for 9 to 12 months, during which her shell will harden again.

After hatching, the prelarvae shortly molt and will begin swimming within a few centimeters from the water’s surface. Their transparent color protects them from predators at this stage. During the following months, the little lobsters molt several times, shedding their old shells to continue growing.

After growing more than a thumbnail, the young will migrate to the ocean bottom and seek shelter among rocks, caves, and grass beds. They also begin wandering outside for food in the first years of life. They reach maturity between 5 to 7 years.

What species can you find in the US?

There are many species available throughout the country, depending on the area. Still, the following are the most well-known to thrive in an aquarium:

• Debelius lobster
• Red lobster
• Feather star squat lobster
• Spiny lobster

The most common species in grocery stores across the US are the following. They are not the best choice for aquariums, but they may do well with adequate care:

• Canadian lobster
• Maine lobster (American lobster)
• French Blue lobster

You can often buy marine lobsters at your local Petco location.

How to keep lobsters in a tank

Lobsters are not recommended for beginner aquarists. It will be easier for you if you have at least basic knowledge about water parameters and supplement dosage.

Tank requirements

Lobsters should have huge tanks. The tank length should be at least 5 times that of the lobster. Of course, larger is better, as it gives the lobster more place to swim.

However, as they are bottom dwellers, the tank doesn’t need to be very tall. The tank should be at least 29 gallons. Water parameters may change quickly in smaller tanks, so provide the largest aquarium possible.

In this article I went into more detail about the various tank types and sizes.

Water flow

Depending on the species, moderate to strong water circulation will be necessary to mimic the conditions in the lobster’s natural habitat.

Water parameters

Make sure you maintain very stable water parameters (pH, nitrate, nitrite, ammonia), as fluctuations may stress the lobster and affect its health. Also, consider adding dissolved oxygen to the tank. Keep the water temperature constant and between 74-80°F. Always ensure it doesn’t fluctuate more than 2 degrees in 24 hours.

Reef tanks

As they are marine creatures, lobsters need saltwater in their tank, an adequate substrate to provide calcium, and a good filtration system. Reef tanks make excellent lobster habitats due to the calcium that corals leak into the water.

Other nutrients your lobster will need are iodine, magnesium, strontium, and trace elements. Iodine is also essential, together with calcium, for healthy exoskeleton development. Lobsters need a tank rich in minerals at all times for a healthy life.

Water changes

Perform regular water changes and check the filter, temperature, and tank equipment daily. Every 2 to 4 weeks, change about 10 – 25% of the total water volume. Test the water quality weekly to make sure it stays at a healthy level.

Hiding places

Live rock can be an excellent addition to the tank and provide natural filtration and natural food source. Add some caves and hiding places for your lobster to feel safe, especially during molting, as the process of shedding the exoskeleton is called. During this period, its new exoskeleton needs extra time to harden, so the lobster prefers to remain hidden.

Substrate

Substrate rich in calcium, such as crushed coral, dolomite, or crushed shells, is recommended. You can also add mineral rocks or calcium supplements, but the substrate can do a great job by itself.

Tank mates

Lobsters are very territorial, so a single lobster per tank should be enough, except if you have a tank the size of a room. Make sure you don’t put it with animals they feed on, like shellfish, clams, shrimp, and small fish.

Some species they are compatible with are angelfish, damsels, killifish, crownfish, cardinals, tangs, butterflyfish, dottybacks, basslets, foxface or rabbitfish.

Avoid keeping them together with mollusks, squid and octopuses. Always introduce new tank mates gradually to the tank and be very cautious when adding other slow-moving bottom dwellers.

Lobsters’ health

A healthy lobster will have a healthy appetite, vivid coloring, and a non-pitted shell and legs.

Matted spots and loss of color are a sign of concern.

Other possible signs of illness are the loss of appetite, spots, lesions or fungus on the body, disfigurement, erratic movements, and missing limbs or antennae.

If you notice that the shell or any body surface shows signs of erosion, immediately check the water to see if nutrient levels are high enough. This may signal a nutrient deficiency of some sort. You can solve this issue by treating the water with the lacking nutrient, performing water changes, or adjusting your lobster’s diet.

Leon the lobster

In November of 2021, Brady Bradwood brought home a grocery-bought lobster to keep as a pet. The lobster was in a poor state and with its claws in rubber bands. While caring for his new pet, Brady shot some great youtube videos. He soon gained popularity and sparked an interest in lobsters as pets. Children began sending him drawings, and people donated for Leon’s welfare. His first video got many millions of views.

Brady brought Leon home packed in a cardboard box, just like any other lobster a regular customer would take home. The animal survived out of water because its gills were still moist.

After getting it home, Brady gently removed the rubber bands off the lobster’s claws, placed it in a tank, and named it Leon. He wasn’t sure about the lobster’s sex but was pretty confident that it was “a dude” as he stated himself. He planned on switching to Leona in case he later discovered it was a female.

During its first days, one claw began gaining a bit of strength while the other claw was still not moving. It took Leon a few weeks to be able to grab something confidently and regain dexterity in its side arms.

The animal’s struggle to regain his mobility fascinated the audience. In addition, the sad reality that this remarkable animal is usually boiled alive and that, if not caught, it can easily live up to 50 years captivated the audience. Brady’s videos will change the way we regard and cook lobsters.

Leon soon began moving shells around as he got more confident with its environment. He ate the algae in its tank, which was quite a lot. It seems lobsters like their greens, so when Brady moved Leon to a new tank, he added seaweed for him to munch on. Leon got a new cave in his new, larger tank, as well as a few rescue killifish as tankmates.

After a few months of growing, Leon began molting. The lobster pushed out of his old shell and began developing a new one. You can see the whole molting process here.

Brady even experimented with a mirror and some cups with food, noticing Leon was quite cautious with them. Brady’s thought was that maybe Leon was well-fed and did not feel the need to investigate the food toys.

Leon looks very happy in this new his new home, as you can see in the videos made by Brady.

Conclusion

A grocery-bought lobster can be an unusual but great pet if you can provide a large enough tank, an adequate diet, and stable water parameters.

If you want to learn more about having crustaceous in an aquarium, you might like our artilce about freshwater panther crabs and blue crayfish with guppies.