Here’s Why Cichlids Stay At The Top Of The Tank


When you know your Cichlids are not top dwellers, seeing them staying at the top of your tank all the time is a concern. It is not normal nor should the situation be left alone.

Cichlid swimming at the top of the tank may be caused by poor water parameters, lack of oxygen, stress, or disease.

It’s important to find out the root cause as soon as you can so as not to lose any fish if you haven’t already.

Why Is My Cichlid Swimming At The Top Of The Tank?

It’s very rare to find top-dwelling Cichlids, although there are a few such as the Sardine Cichlid (Cyprichromis leptosoma), a Lake Malawi Cichlid. But most Cichlids live in the middle to the bottom part of the tank. Here are the reasons why a Cichlid stays at top of tank.

Reason #1: Lack of oxygen

If you find your Cichlids with their noses pointed up near the surface and gasping for air, there’s not enough oxygen for them to breathe.

Like all animals, fish need oxygen to survive. Fish do not inhale the bubbles your air stone or filter creates. They inhale dissolved oxygen in the water. And to create dissolved oxygen, bubbles “disturb” the top of the water through surface agitation.

What Is Surface Agitation?

Surface agitation creates gas exchange by the surface of the water when carbon dioxide (exhaled by fish) is released and oxygen (from the surface) is taken into the water. Therefore, the more water surface you have, the more dissolved oxygen is available for your fish to breathe in.

This is the reason why having a bigger tank for Cichlids is ideal. A 125-gallon long obviously has more water surface than a 55-gallon.

Since there is more dissolved oxygen at the top of the tank, Cichlid finding it hard to breathe will swim near the top as more oxygen is present where the gas exchange happens.

However, fish are not the only living things inside your aquarium that breathe in oxygen. That good nitrifying bacteria in your aquarium use up dissolved oxygen even more so than your fish. If you have an algae bloom, this may block the gas exchange happening on the water’s surface.

Reason #2: Poor water chemistry

Other than Cichlids and living organisms finding it hard to breathe, water that has a low amount of dissolved oxygen also decreases pH levels. Once the pH lowers to 6.0, your Cichlids will exhibit cloudy eyes and lethargy.

Here’s Why Cichlids Stay At The Top Of The Tank
Here’s Why Cichlids Stay At The Top Of The Tank

Next, look at your thermometer. Water with a temperature that is too high lessens the amount of dissolved oxygen it contains. Yes, Cichlids need a higher temperature than other fish, but don’t go beyond 82 deg F to ensure that they can breathe.

Are you performing your regular water testing? Your kit should show you if there’s a presence of ammonia in the water. This should stay at 0ppm, but 0.5ppm should not be enough for you to panic. However, higher rates will start to burn your Cichlid’s gills and eventually kill them. Thus, you’ll see them at the top of your water. If they could scream for help, they would be doing so.

Reason #3: Stress

And since fish can’t speak, much less scream, you won’t hear them call on you if they’re being bullied. A stressed fish tend to stick to one part of the tank, including a corner of the surface. Observe your Cichlid for any visible injuries such as torn fins or lacerations.

If you have signs of aggression such as these, you may be overstocked. More fish means a higher demand for air.

Stress may also be caused by disease. Two common diseases that may cause a Cichlid (or all of them) to gasp near the surface are ich and velvet. Both of these are parasitic conditions that must be treated right away.

Ich presents itself as white, salt-like spots all over the Cichlid’s body. On the other hand, velvet looks like gold dust sprinkled on the fish, which is another name it is known by.

How To Cure Or Prevent Cichlid Swimming At The Top Of The Tank

We hope none of your Cichlids have died yet. But regardless of the situation, take immediate action to prevent further problem escalation.

Cure Or Prevent Cichlid Swimming At The Top
Cure Or Prevent Cichlid Swimming At The Top

Tip #1: Test, test, test

Regular water testing should be a part of your maintenance routine. Strips are good and inexpensive, but any sign of abnormality should warrant the use of the more accurate Master Test Kit. As we mentioned above, ammonia should be kept at 0ppm. Nitrates should be 20ppm or lower. Your pH should stay between 7.5 to 8.5.

Tip#2: Do a major water change

If you find your pH has lowered or your ammonia (or even nitrate) has spiked to intolerable levels, you need to do a major water change quickly. Replace at least 50% of the water and keep doing this daily until your tests prove that the water has returned to safe levels.

Tip #3: Upgrade to a bigger tank

Pet store attendants may not always give you accurate information about your fish. Keeping Cichlids is popular, but you have to do your research. These fish may grow quite big so you should have the right-sized aquarium to accommodate them at maximum length (mature size).

For those who have both genders of a species, consider providing enough space for fry. Convict Cichlids are particularly notorious for pairing up and making babies.

If you’re overstocked, you should either buy a bigger tank or rehome some of your Cichlids.

Tip #4: Add surface agitation

Your filter water turnover should be enough for your tank. The more flow, the more surface agitation you get. You may find out more about using the right filter for your Cichlid tank in our previous post “Are Sponge Filters Good for Cichlids”.

Increase the flow of your filter if it’s too slow. Cichlids like some horizontal flow anyway, but not too much.

One of the benefits of increasing the amount of dissolved oxygen in the tank is that the nitrifying bacteria will thrive and do a better cleaning job of waste products in your aquarium.

Tip #5: Treat diseases ASAP

Upon confirming the presence of ich or velvet, quarantine the infected fish and clean the main tank.

While aquarium salt baths may help a Cichlid with ich, you may need copper treatment not just for the infected fish but for the whole tank. Keep in mind, both diseases are contagious.

During treatment, plants will be affected by copper, so either you get a plant-safe ich treatment or treat all infected fish in a hospital aquarium.

If you choose to medicate in the main tank, remove your carbon filter so it can’t limit the effect of the medicine.

Tip #6: Consider adding a UV sterilizer

A UV sterilizer will not endanger your good bacteria as most of these live on surfaces. The device is submerged in water and can kill harmful organisms floating in the water. They’re particularly useful against algae.

Yes, they are pretty expensive and the bulb needs to be replaced now and then. You may only run them occasionally or use a low-wattage bulb to keep costs down.

Please note that having a UV sterilizer (or two) is NOT a substitute for filtering your water and cleaning your tank.

If you are interested in learning more about your fish behavior, check out the links below:

Whew, You Can Breathe Now

We hope you found what’s keeping your Cichlid near the top of your tank. If not, you can send us a message and we can figure out your specific situation better. Until then, stay safe.

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