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Why Is My Rainbow Shark Not Moving? (7 Causes)

Why Is My Rainbow Shark Not Moving? (7 Causes)

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This post is written to the author's best knowledge and is not intended to be used in place of veterinary advice. In addition, this post may contain affiliate links. As an Amazon Associate I earn from qualifying purchases.

Owning rainbow sharks is satisfying for many different reasons. Many people say that these fish are some of the best to own from an aesthetic perspective.

You might love the look of these fish or you simply might enjoy observing them in the tank. When your rainbow shark stops moving, you’re going to be concerned that something is amiss.

Normally, rainbow sharks are somewhat active fish that will swim around at the bottom of the tank. What does it mean when this fish stops moving as normal?

Read on to learn about reasons why this happens. It’ll help you to troubleshoot the situation to determine what is going on.

1 – Stress

Stress can easily cause rainbow sharks to start doing unusual things. Sometimes stress will cause rainbow sharks to start glass surfing, but it can also simply make them lethargic.

There are so many things that can cause rainbow sharks to feel stressed in fish tanks. You want to try to limit stress in the tank since it has the potential to make your fish sick.

Below, you’ll learn about some of the common things that cause rainbow sharks to feel stressed. Later, you’ll learn more about other things that might cause fish to stop moving in the tank.

2 – Tank Size Issues

The tank size can sometimes cause stress. Rainbow sharks are fish that need a lot of room to be comfortable in an aquarium.

If you buy a fish tank that’s too small for rainbow sharks, it’s not going to be a good situation. For example, a rainbow shark would be extremely stressed if you tried to force it to live in a 20-gallon fish tank.

The minimum tank size for a rainbow shark is said to be 50 gallons. However, many experts say that it’s better to go with a 55-gallon fish tank.

The aquarium should be 48 inches long as well. You want to give the fish plenty of space so that it can feel comfortable in its new home.

Even if the tank is large enough, you should never overcrowd the tank. You don’t want to try to cram too many fish in the tank or you’ll encounter so many problems.

Understand that rainbow sharks are aggressive and territorial fish. They need a lot of room and they loathe being kept in overcrowded fish tanks.

You can keep these fish in tanks with other fish, but you need to avoid putting too many fish in one tank. Make sure that you give the fish more than enough room.

If you were careless and crammed the tank full of fish, this might be the reason why your fish isn’t moving. It could simply be that the fish is stressed and fed up with the situation in the tank.

3 – Improper Tank Mates

Improper tank mates might cause your fish to stop moving as well. All fish are going to have fish that they’re compatible with and fish that they’re incompatible with.

Rainbow sharks can be kept in community tanks, but you need to keep them with compatible tank mates. Otherwise, the fish will potentially get into fights with the other fish.

There are many popular fish that simply cannot be housed with rainbow sharks. Bettas are a good example.

It’s likely that rainbow sharks would fight with the bettas. They also can’t get along with many types of cichlids.

In some cases, you might put rainbow sharks in tanks with fish that will bully them. When this occurs, the fish might choose to hide in little caves and they’ll stop moving.

Avoid situations such as this by choosing only appropriate tank mates for rainbow sharks. Note that rainbow sharks don’t even do well living with other rainbow sharks unless the tank is extremely big.

4 – Dietary Issues

Dietary issues can make your fish get so stressed that they will feel lethargic. If your fish isn’t moving much it could be due to problems with its diet.

Have you been feeding the fish often enough? Rainbow sharks are meant to be fed two to three times per day.

Most experts say to feed the fish three times per day because it’s safer. You can feed the fish as much as they can finish in five minutes.

These fish need to be fed foods such as algae wafers, veggies, and live meaty foods. You can feed them wafers daily and then supplement the diet with other foods.

Make sure that you’re feeding the fish often enough so that they can do well under your care. If you don’t feed them properly they won’t have enough energy to be active in the tank.

5 – Water Quality Issues

Problems with water quality can make these fish get so stressed that they will stop moving. Understand that rainbow sharks are fairly sensitive to water quality issues in the tank.

They need the water temperature to remain between 72 degrees Fahrenheit and 79 degrees Fahrenheit. You need to keep an eye on the pH balance to ensure that it stays between 6.5 and 7.5.

Keeping things in order involves testing the water, doing regular water changes, and cleaning the tank. It’s also best to buy a powerful filter for the tank to make your life easier.

Focus on fixing any issues with water quality as fast as you can. This is one of the most important aspects of caring for fish.

6 – Illness

Illness can make fish stop moving. You should know that when fish become stressed they’re more likely to get sick.

When fish get stressed it suppresses their immune systems. It makes it so that they’re susceptible to various diseases and infections.

Many common fish illnesses have symptoms such as lethargy. Sometimes fish will lose their appetites and will simply hide in the tank when they’re sick.

So if your rainbow shark isn’t moving, it’s possible that it might be sick. You’ll need to look out for other symptoms to try to determine exactly what is wrong.

Rainbow sharks can be treated and you can get them back to being healthy again. However, you need to be careful when treating these fish since rainbow sharks are scaleless fish.

If necessary, you can reach out to an exotic veterinarian that treats fish. This will allow you to get professional advice on how to proceed.

7 – Sleeping

You should also consider whether your fish is simply sleeping. Fish will sleep from time to time.

Rainbow sharks are known to rest during the day. They’ll hide in caves or among aquatic plants and take naps.

So you could simply be noticing that your fish isn’t moving during its normal sleeping time. All fish seem to have times when they’re more active and times when they’re more likely to rest.

Check to see if your fish is simply sleeping. If you try to move the water a bit near where the fish is sleeping it’ll likely stir and start moving.

Is the Rainbow Shark Dead?

Sadly, a rainbow shark that isn’t moving at all might be dead. Has your fish passed away?

If the fish isn’t moving at all and it doesn’t appear to be breathing, it could be that the fish has died. You can check to see if the fish shows any signs of moving by touching it with an aquarium net gently.

When the fish doesn’t react to anything that you do you’ll know that it has passed away. It could be that the fish was sick and died of some type of illness.

Rainbow sharks can also die of old age. Most rainbow sharks live between four and six years in captivity, but they can live a bit longer than this with exceptional care.

When these fish receive poor care they might not even survive for two years. It all comes down to how much effort you’re putting into caring for the rainbow shark.

Final Thoughts

You should feel more confident that you can figure out what’s going on now. Many things might cause rainbow sharks to stop moving in the tank.

The fish could simply be stressed due to problems in the tank. Or it might be sick and it needs some type of treatment.

You should also consider whether the fish has died. If the fish isn’t moving or breathing, it might have passed away and you’ll need to remove it from the tank.

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