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6 Reasons Your Rainbow Shark Is Swimming Vertically

6 Reasons Your Rainbow Shark Is Swimming Vertically

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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.

Purchasing rainbow sharks for your home aquarium should be exciting. You know that these fish look really nice and you’re glad to have them in your tank.

You want to do your best to keep the fish happy and healthy in your aquarium. This is why you’ll be worried when you see your rainbow shark acting oddly.

Has your rainbow shark been swimming vertically as of late? Perhaps you’ve seen it swimming up the glass of the tank.

Is this a bad sign that things aren’t right in the tank? Or is swimming vertically normal behavior for rainbow sharks?

Keep reading to get to the bottom of this situation. It should be easy to figure out what’s going on so you can turn things around for the fish.

Swimming Vertically Isn’t Normal

Swimming vertically isn’t generally seen as normal for rainbow sharks. It’s a bit of an unusual action that likely indicates that something is wrong.

Rainbow sharks are territorial fish that need lots of space in the tank. They generally hang out at the bottom of the tank and will swim around down there.

Swimming up the glass isn’t typical unless the fish is stressed in some way. So if you’re seeing the fish swim vertically in your aquarium, it’s very likely that your fish is stressed due to problems in the tank.

When fish swim up and down the walls of a fish tank it’s referred to as “glass surfing.” Essentially, the fish is looking for a way out because things aren’t right in the tank.

What causes rainbow sharks to become stressed? Read on to learn more.

1 – Is the Tank Too Small?

The fish tank might be too small for rainbow sharks. Rainbow sharks become extremely stressed when they’re forced into small tanks.

These fish are territorial and they like to have plenty of space. One rainbow shark should be kept in a 50-gallon tank or something larger.

Many enthusiasts recommend going with an even bigger tank. So you might want to avoid rainbow sharks if you don’t have room for a decently-sized tank in your home.

This isn’t a situation where you can try to force the rainbow shark into a fish tank that’s a bit smaller. It’ll only lead to poor results and you don’t want to make your rainbow shark suffer.

2 – Overcrowding in the Tank

Overcrowding in the fish tank can be an issue as well. Even if you technically have the right tank size for a rainbow shark, it’s possible to cram it full of fish and cause the fish to become stressed.

Rainbow sharks can be kept as community fish, but you need to give them enough space. If you cram the fish tank too full of fish it’ll cause big problems.

The rainbow sharks will become more territorial and their stress will continue to worsen. This could make the fish get sick since stress negatively impacts the immune system.

You need to make sure that you don’t go overboard when stocking the aquarium with fish. Ensure that all of the fish in the tank have more than enough room.

3 – A Lack of Hiding Spots

You’ll find that rainbow sharks enjoy hiding in the tank. They don’t hide all the time, but they utilize hiding spots for various reasons.

Sometimes these fish like to sleep in little hiding spots such as caves. They’re also territorial fish that like to defend caves and other spots that they’ll claim as their turf.

A lack of hiding spots in the tank could make the tank less appealing to the fish. They might be unhappy if the tank is bare and doesn’t have places for them to hide.

So vertical swimming could be a sign of this stress. You might want to put cave decorations and aquatic plants in the tank to make these fish feel at home.

4 – Water Parameter Issues

Issues with the water parameters will make it hard for your fish to thrive. If your fish are being kept in dirty water, it makes sense that they would want to escape.

Rainbow sharks are a bit sensitive to problems with water quality. You need to make sure that you monitor the water parameters closely.

The water needs to remain clean and you need to ensure that the temperature of the water doesn’t fluctuate. Problems with the water parameters can easily stress the fish and make them start glass surfing.

The pH balance must remain between 6.5 and 7.5 for the rainbow sharks to stay safe. Use a high-quality heater that can keep the temperature of the water between 72 degrees Fahrenheit and 79 degrees Fahrenheit.

Test the water regularly using pH balance testing strips for fish tanks. This will allow you to make adjustments if anything is off.

Of course, regular tank maintenance is crucial as well. You need to clean the tank and do regular water changes to protect your fish.

5 – Improper Tank Mates

Did you make the mistake of putting your rainbow sharks in tanks with fish that they aren’t compatible with? This is a bad idea since it can lead to various issues.

You’ve already learned that rainbow sharks are aggressive and territorial fish. This can lead to them having problems with various other types of fish in community tanks.

These fish can be kept in community tanks, but you need to put them with compatible fish. If you put them with incompatible fish, it might cause severe stress issues.

Also, you should know that it’s common for rainbow sharks to fight with various types of incompatible tank mates. This could cause your fish to get hurt or even get killed.

So take the time to research things thoroughly before moving forward with a community aquarium plan. You want to get things right and avoid putting any of your fish in danger.

6 – Dietary Issues

Sometimes dietary issues can cause fish to start doing strange things. Glass surfing might occur if the rainbow sharks aren’t being fed well.

These fish need to be fed algae wafers, veggies, and live meaty foods. The algae wafers are the common daily food that you feed these fish, and you’ll supplement the diet with the other types of food.

You’re supposed to feed rainbow sharks three times per day. Generally, it’s best to feed these fish as much as they can eat in five minutes.

If you haven’t been feeding them the right food, they might try to escape to find better food options. Focus on feeding your rainbow sharks appropriately to see if it helps.

Final Thoughts

Now you know that many types of stress can cause glass surfing in rainbow sharks. Rainbow sharks can get stressed due to being kept in tanks that are too small or having to live in poor water conditions.

Simply do your best as a fish tank owner to keep your rainbow sharks safe. Handle the basics well and you shouldn’t see your fish swim vertically in the tank very often.

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