Angelfish Water Current: Do They Like it?

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We all know that angelfish can hover in place. That is an interesting phenomenon since not all fish can do so. However, from what I have seen, sometimes they do so due to harsh currents. That was when I began to wonder whether or not currents are necessary for angelfish, or if they like it at all.

Yes, angelfish do like water currents. That is because flow elevates oxygen concentration and removes waste. Nevertheless, strong flows may also stress your fish and prevent them from eating. Balancing it mainly focuses on the GPH, which resembles the amount of water flowing through the filter each hour.

As we move forward in this article, I will present to you a few warning signs that may indicate that the current in your tank harms your angelfish. Also, I will share with you a few techniques to better control it, based on years of experience.

Also Read: Facts About Angelfish

Do Angelfish Like Current?

Most fish expect a current of some sort in their tanks. With angelfish, it isn’t a question of whether or not they like flow but, instead, the strength of the current. Angelfish live in slow-moving water in the wild. 

As such, it isn’t a good idea to expose them to a strong current in the tank. That being said, people who expose their fish to fast-moving waters rarely do so on purpose. The flow in an aquarium is determined by the filtration system (which I will elaborate more deeply later on). 

For now, you should know that the right flow rate can have a drastic impact on your angelfish, bringing benefits such as the following:

  • Oxygen – Because the filters are designed to move the water around, they are going to affect the oxygen levels in your tank. To be more specific, a reasonable flow rate will increase and improve the distribution of oxygen in your aquarium.
  • Filtration – The flow rate also affects filtration. A decent flow rate allows the filter to remove waste in a timely and efficient manner. A low flow rate does the opposite.

However, you should keep dead spots in mind. Tanks typically feature these places where the water doesn’t move much. Dead spots are a problem because the water can become stale. An active filter with a decent flow rate will eliminate dead spots, preventing them from manifesting in the first place. 

A tank should mimic the natural environment of your angelfish. This is the only way to ensure that the angels thrive. The right flow rate will help you replicate the angelfish’s natural habitat, which is the Amazon Basin.[1]

The right flow rate is supposed to improve the overall quality of your water. But this is why it is so challenging to select the proper flow rate. You must balance the needs of your fish with the requirements of the tank water. 

In other words, you must find a flow rate that maintains the quality of your water without creating a current that is too strong or too weak for your angelfish. Finding that balance is difficult. You must keep the following factors in mind:

  • GPH – This refers to the Gallons Per Hour.[2] It is also the official term for a filter’s flow rate. As its name suggests, the GPH tells you the number of gallons that will flow through a filter in an hour. For a filter to remove waste, the water in the aquarium must flow into it.

This is what creates the current. The GPH is determined by factors like the type of filter, its strength, and its efficiency. A high GPH makes for a more powerful filter because you are filtering more water each hour.

Generally speaking, a decent filter should cycle through the tank’s entire volume at least four times in an hour. The more times the water is filtered in an hour, the better. Regarding angelfish, I would suggest getting a filter with a GPH range of 150-200.

  • Turnover rate – The GPH determines the volume of water that flows through a filter every hour. The main objective is to cycle all the water in the tank through the filter multiple times an hour. However, there is no guarantee that all the water in the tank will reach or transition through the filter.

It is possible for a filter to suck in the same water it just spat out. The Turnover rate defines the actual efficiency of a filter. It takes into account how much of the water in the tank it actually filters. Nevertheless, if your tank doesn’t feature many obstacles, you may rely on the filter’s GPH.

As was mentioned above, dead spots are bad because they can make the water stale. Stale water encourages the growth of dangerous organisms. You need a robust filtration system with a decent flow rate to combat dead spots. 

  • Obstructions – You cannot eliminate dead spots by merely using more powerful filters, not in angelfish tanks. This is because angelfish prefer planted tanks with plenty of foliage and decorations. 

The presence of these obstructions can complicate filtration, encouraging the manifestation of dead zones. People who have too many plants are expected to use multiple filters. This is the only way to eliminate dead spots with certainty. 

You must base your choice of a filter and GPH rating on the needs of your angelfish. You cannot apply the same flow rate to all fish. Different fish have different needs.

As such, you are discouraged from blindly using the flow rates and filters that produced positive results in the tanks of other fish owners, unless those fish owners are also rearing angelfish.

Can a Strong Current Hurt My Angelfish?

Then again, some people cannot help but wonder whether strong currents are really that important a consideration. They tend to dismiss the consequences that an intense flow rate can attract. However, this is a mistake.

If you expose your angels to an excessively strong current, you can expect a few troubles down the line. In fact, they are pretty similar to what happens in other fish, like bettas.[3]

First of all, a high flow rate will exhaust your angels because they must exert a lot of effort to swim against it. Imagine walking all day while a strong wind tries to push you back. This is what your fish experience whenever you expose them to a harsh stream. 

Keep in mind that tired fish are stressed fish. As you know by now, stress is terrible for angels. But this is what will manifest if they have to keep swimming against a strong current. Eventually, the consistency of the pressure will weaken their immune system, exposing them to unsavory diseases. Also, tired angels are less likely to spawn. 

Secondly, if the current is too strong to permit the angelfish to reach and stay at the top of the tank, eating will become a challenge. The situation will become even worse if the current becomes so strong that it keeps pushing the food away from your angels before they can eat it. 

How Can I Know if The Currents Are Too Strong for My Angelfish?

You cannot expect hungry, tired, and stressed angelfish to remain healthy. Of course, whenever you discourage fish owners from making the current in the tank too strong for their fish, they cannot help but wonder how they are supposed to determine that their filter’s flow rate is too high.

You cannot expect them to simply wait until their fish grows ill from hunger, stress, and fatigue. They need to act early on before the current does lasting damage. But it is also a mistake to make alterations to your filtration systems to protect your fish from a strong current when that current wasn’t that strong, to begin with.

You need to ensure that you only adjust the flow rate when your angels need it. Fortunately, you can rely on your fish to tell you when the current has become too challenging:

  • Look at the angle at which your angelfish is swimming. It should be swimming straight. But if it looks like it is moving through the water at an angle, the current is probably too strong. 

You should talk to an expert before taking any drastic steps. Conditions like dropsy and constipation can cause similar reactions. I have previously discussed that topic in a different article, where I explained how to tell that your angelfish is pregnant. I highly suggest that you read it before making drastic changes to your tank.

  • If the angel keeps avoiding certain areas of the tank, the current in those areas is probably too strong. Some fish will simply remain in the same spot because most regions of their aquarium are plagued by flows that are too strong. 

Angelfish can hover in place for any number of reasons. But if you get the sense that the angel is avoiding individual sections, take another look at your filtration system. If you don’t, there is a chance your angels will miss their flakes, which are naturally drifting.

  • A high flow rate is going to force your angels to hide behind obstructions like plants and decorations because they can protect them from the current. If there is no other reason for your angelfish to hide (as predators), perhaps you are better off with a smaller filter.

Also Read: Can Angelfish Change Colors?

How Can I Adjust The Currents for My Angelfish?

If you know that the current is too strong, you can take steps to reduce it.

My first recommendation would be to use Hang on The Back filters.[4] These typically provide a slower flow rate, especially if you match the filter to a tank of the right size. You should look for cleaners that permit you to adjust the flow rate (an example of that would be canister filters).

If you don’t want to buy a new filter, try placing a clean pantyhose over the intake tube. Once it has been secured, the pantyhose will debilitate the amount of water entering and leaving the system, reducing the strength of the current.

Another solution would be using a foam or mesh. Place it at the tank’s outlet to control the flow rate. That might also lower the noise your filter produces. Nevertheless, make sure not to block the filter’s entrance. This may compromise the whole filtration process and elevate Ammonia and Nitrates. 

You can also directly adjust the flow rate by using powerheads. You can pair them with under-gravel filters instead of using air stones. Powerheads enable you to increase or reduce the flow rate. 

How Does Filtration Work in Angelfish Aquariums?

As I’ve already mentioned, harsh currents could harm your angelfish. You may adjust your filter and lower the flow once you notice the warning signs above. However, you should know that there are other ways for water filtration.

Filtration comes in three forms, namely:[5]

  • Mechanical – These are physical devices that remove particulates from the water, trapping them in the process. Mechanical filters should be washed regularly to prevent them from accumulating waste. A dirty filter is going to corrupt your tank, introducing ammonia to the water.
  • Biological – Biological filtration doesn’t remove visible particulates. Instead, it nurtures bacteria that maintain the water parameters by turning toxic ammonia into nitrates, which are less toxic. 
  • Chemical – This form of filtration involves the use of chemical products that are introduced to the water to remove dissolved waste. Charcoal is one of the most common chemical additives on the market today. 

Of all these filtration methods, mechanical filtration is the most important, at least as far as the current is concerned because it affects the rate at which water flows. However, even when you lower the power (or use a smaller filter), filtration may still occur. That is primarily due to vegetation and the biological system you have grown in your tank so far. 


Angelfish originated from the Amazon Basin, which naturally features water currents. That is how we are able to conclude they like water flows and probably need it. When the water doesn’t stand still, oxygen is able to dissolve, and waste is being washed away.

However, strong flows may also stress your angelfish, preventing them from eating and reproducing. When you notice your angels hide or stay away from certain areas in your tank, you should act to lower the power. The best choice is getting an adjustable filter from advance.

I hope my article has shed some light on whether or not angelfish like current, and how to deal with issues it may arise. The best approach here is experimenting, and by that learning to know what is best in your particular tank.

Also Read: What Do Angelfish Do In Fish Tanks?