Copepods are living organisms that are mostly found in aquarium environments and marine ecosystems. Some of their most common names are roly-poly and pill bugs. Most of them are usually harmless, as they are also free-living.

Mostly, these organisms feed on algae and detritus, and never have any conflicts with other organisms. Unfortunately, some of them are parasites and can be harmful to other marine organisms.

Fish often feed on copepods. They are an excellent nutrient source for fish as they feed entirely on algae and other naturally occurring foods within the marine ecosystem.

These organisms may oftentimes appear in aquariums and should not be a cause for alarm. Most of them usually feed on diatoms, and they can get into crevices that are hard to reach while doing a regular cleaning of the aquarium.

Every aquarium owner needs a clean tank to maintain a healthy environment for the fish and other aquarium inhabitants. It is impossible to use detergents and disinfectants to clean the tank with fish in it.

Therefore, copepods come in handy as they help to get the job done to near perfection, as one copepod alone can clear up to hundreds of thousands of diatoms in a day.

When to introduce copepods in aquarium

Sometimes it may be necessary to introduce copepods in an aquarium, especially if the rate of diatom build-up is quite high. The build-up can be monitored by the greenish-looking slime on the glass surface. This is mostly organic waste that is food to copepods.

The best way to introduce copepods in such situations would be at night when the fish cannot spot them easily. It is advisable to first feed the fish to prevent them from rushing to eat the copepods before doing their job of cleaning the tank’s surface.

It would be best to release the copepods as close to the substrate as possible to facilitate their proximity to the food source. Diatoms often build up on the tank’s surface and the substrate where fish feces often drop, and facilitate the formation.

There is no specific recommendation for the volume of copepods per tank as the organisms often multiply at a very high rate.

Are too many copepods in an aquarium dangerous?

How much is too much? You may be wondering. There is never anything like too many copepods. Copepods often self-regulate according to the available food sources. Their numbers entirely depend on the amount of waste in the tank.

If they seem too much, the tank must be full of waste. How does it feel to have an extra workforce that does not demand any pay, yet they get the work done perfectly? Most of them will be eaten by the fish, anyway.

Copepods supplement fish diets, and the more they multiply, the better. Their big numbers will supplement food for the fish. Being that they are living organisms makes them a highly nutritious food supplement for the aquarium fish. They may also help in boosting fish populations in the tank. Is that not awesome?

How to grow copepods in an aquarium

The best way to introduce copepods in an aquarium is to go for the commercial aquacultured types. They are usually well-nourished and biologically tested to avoid the parasitic types.

The culture can be poured into the aquarium using a feeding tube that reaches the substrate. The copepods will easily settle on the substrate using this method. These organisms will begin reproducing as soon as they start feeding.

The whole action should be done at night to avoid the fish from eating most of the newly introduced copepods. It must also be done after feeding the fish well enough.

These organisms often lay microscopic eggs that the fish cannot spot. The eggs will also hatch into larvae that are still too tiny for the naked eye. The larvae often grow very fast and soon become adult copepods.

All this while (from the larval stage), the copepods will be feeding on the aquarium waste. In summary, they begin their cleaning duties at the larval stage.

Are copepods good for freshwater aquariums?

Freshwater aquariums are home to a wide variety of fish and other aquatic organisms. They also experience a lot of waste build-up that requires regular cleaning. Notably, cleaning an aquarium may require an extra input that may not always achieve the desired results.

Therefore, adding copepods to a freshwater aquarium may be critical in enhancing the outcomes.

Being that copepods are an excellent food source for fish, they may help in supplementing the food sources of freshwater fishes. Unlike other foods that are added to the aquarium, these living organisms do not leave the tank dirty despite being a food source.

Freshwater fishes are highly sensitive compared to saltwater fishes. Also, a lot of waste build-up in the freshwater is likely to interfere with the freshness. Therefore, it is critical to have a reliable system of cleaning a freshwater aquarium to ensure that the fish in the tank live in a near-natural ecosystem.

How do I know if I have copepods in my tank?

Copepods can sometimes appear in a tank naturally without being introduced by the tank owner. In most cases, they are usually carried in live sand and rocks without the knowledge of the tank owner.

Upon the sand or rocks being introduced into an aquarium, one is likely to notice copepods. They were most likely brought there as larvae or eggs, and could not be spotted by the naked eye.

In most cases, they often bloom in slightly warm temperatures that favor their growth. They are also dependent on the availability of food sources to bloom successfully.

Some copepods might be too tiny to spot immediately. However, the most practical way to spot them is to turn off the pump at night to eliminate bubbling, then shine a spotlight through the glass. The copepods will most likely swim towards the light. This way, you will know if you have them in your tank or not.

What do Copepods eat?

Copepods in the marine environment are equivalent to cattle in dry land. As cows feed on grass, they feed on phytoplankton, which grow naturally on the substrate. These organisms also convert the sun’s energy into food to be used at the higher trophic levels.

It is critical to note that these organisms do not necessarily need sunlight to survive. However, they need algae to supplement their diet.

Larger versions of copepods are known as amphipods. These can consume a variety of wastes that include fish waste. They also eat most of the waste that forms and sticks onto surfaces and substrates.

Please note that even the larger copepods are not really large, and can squeeze into tiny spaces and reach for the waste in those spaces.

How to get rid of copepods in freshwater aquarium

Some aquarium owners view copepods as pests, yet they are not. These tiny organisms help in cleaning the aquarium as well as acting as an extra food source for the fish.

Given that they feed on algae, this makes them even more nutritious and valuable for the fish.

Eliminating copepods from the aquarium is easier than it may seem. Some of the steps include:

Siphoning

Copepods are generally attracted to light. Shining a spotlight on the tank in the dark will attract them, and they will swim towards the light source. They can be easily siphoned or sucked out of the tank using a suction pump and a PVC pipe.

Avoid overfeeding the fish

Less feeding of the fish reduces the volumes of waste disposed daily. A scarcity of food sources translates to a reduction in the populations of copepods within the tank.

Introducing predators

Certain freshwater fish species, especially the smaller ones like guppies, mollies, and tetras, are excellent copepod eaters. They can easily spot these tiny organisms that may be difficult for bigger fish to spot.

Copepods in a reef tank

It is critical to know that coral, despite having the appearance of a colorful plant, is actually an animal. It is a colony of various living organisms connected to each other and are symbiotically related. These connected organisms form what is commonly referred to as a reef. They also require nutrition for their daily living.

Copepods are critical in all reef tanks for various ecological reasons. First, these organisms act as grazers, feeding on microscopic microalgae. The second function is that they act as scavengers, where they feed on detritus. Finally, they act as food for certain zooplankton.

Copepods provide coral with an excellent food source, particularly supplementing the fatty acids that they extract from the microalgae. They also help to clean the microalgae off the reefs to allow the coral to breathe with ease.

Copepods also act as recycling plants in reef tanks. They consume the waste produced by coral and convert it to nutrients that are consumed again by the coral that feeds on the copepods.

Copepods also help in maintaining the water quality for coral. It is difficult to determine if the water quality is not fair to coral. Therefore, a natural means of maintaining the water quality might do more good for the coral. It is advisable to have as many copepods as possible in a reef tank to improve the health of the coral.

Copepods in a shrimp tank

Shrimps are not known to go after copepods. It is also apparent that shrimps produce waste, and are likely to have grime in their tanks. It may not be uncommon to spot large colonies of copepods in a shrimp tank due to the availability of food sources alongside the lack of a natural predator.

The presence of copepods in a shrimp tank must not be a cause for alarm as they are rarely harmful to shrimps.

If you are not interested in having copepods in a shrimp tank, it may be advisable to introduce more friendly fish that will not feed on the shrimps but can eat the copepods.

This introduction of such fish may be applied as a temporary remedy, and the fish can be returned to their tanks after they have completed their duties of eliminating or reducing the copepod populations.

Are copepods good or bad?

Copepods are an excellent addition to an aquarium anytime. These organisms will not only clean your aquarium, but will also supplement the fish’s diet in the aquariums that they inhabit.

Most people view them as invaders, and some even refer to them as fish lice. The name might seem put off the interests of many who might not know their benefits. However, it is recommended to weigh the benefits of these organisms against their negative aspects.

Imagine copepods as workers providing free labor and still contributing towards ensuring that you and your family get enough food to sustain you.

Simply put, their benefits are way more than can be imagined.

References

Algae Barn: Benefits of Live Copepods

Life of Fish: How to Get Rid Of Copepods in Fish Tank? | Aquarit’s Secrets

Reef Hacks: The Smallest Hack for the Biggest Results: Reef Hacks Guide to Copepods.