Firefish Care: Tank Setup, Diet, Tank Mates, Diseases & More!

Firefish, also known as Lionfish, are stunning marine creatures native to the Indo-Pacific region. With their beautiful fan-like fins and striking color patterns, they make a popular yet challenging addition to many saltwater aquariums.

Firefish require a tank size of at least 20 gallons, with a temperature range of 72-78°F and a pH range of 8.1-8.4. They are carnivores and need a varied diet of high-quality frozen or live foods such as brine shrimp, mysis shrimp, and krill. They also require a well-lit aquarium with plenty of hiding places and live rock.

In my own experience with keeping firefish, I’ve found that understanding their unique needs is crucial for providing the best care. They require a more specific water environment, diet, and tank setup compared to other fish species.

In this article, we’ll explore the essentials of firefish care, including tank set up, water conditions, and feeding regimen. Stay tuned for tips that will help your firefish thrive and add a touch of elegance to your aquarium.

Firefish 3

Species Summary


Firefish, also known as Nemateleotris magnifica, are saltwater fish originating from the Indian and Pacific Oceans. They are commonly found around coral reefs at depths of 20 to 200 feet.


In captivity, Firefish have an average lifespan of 3 to 5 years if provided with proper care. I’ve personally seen some live even longer, but that’s relatively rare.


Firefish are known for their striking appearance, with a vibrant red-orange front half that transitions to a white-yellow shade toward the tail. They also possess a slender body and an elongated dorsal fin.


These fish remain quite small, growing to a maximum size of 3 inches in length.

Growth Rate

Firefish have a relatively fast growth rate, typically reaching their full adult size within 6 to 12 months.

Behavior & Temperament

Generally peaceful, they are a great addition to community tanks. However, they can be territorial with their own species and should be provided with plenty of hiding spots to avoid conflicts. Firefish are known to “dart” into hiding when threatened or startled.

Male Vs Female

Distinguishing between male and female Firefish can be difficult since they don’t have significant differences in appearance. However, males tend to be slightly larger and have a more elongated first dorsal fin.

Tank Setup

Tank Size

A suitable tank size for Firefish is important. I once had a Firefish in a tank that was too small and it became stressed. Minimum tank size should be 20 gallons (75 liters).


Firefish prefer a dimly lit tank, so opt for low to moderate lighting. Avoid intense lights; ensure hiding spots for comfort.

Filtration & Aeration

Install a quality filtration system to remove waste and maintain water quality. Add an air pump to ensure good oxygen levels in the water.


Firefish need a stable temperature between 72-78°F (22-25°C). Use a reliable aquarium heater with a thermometer to monitor.


Choose a soft, sandy substrate to avoid damage to the Firefish’s delicate belly.


Provide hiding places with rocks, caves, or PVC pipes. Make sure to leave open swimming areas too.


Living or artificial plants will enhance the environment. Firefish enjoy plants for cover and security.

Water Quality

Water Temperature

Firefish thrive in water temperatures between 72-78°F (22-25°C). A stable and consistent temperature is crucial for their well-being. I remember when I first started keeping Firefish, I didn’t monitor the temperature as closely as I should have, and my fish started acting sluggish. After a quick temperature adjustment, they were back to their usual active selves.

Water PH

Maintaining the right pH level is essential for Firefish. They prefer a pH range of 8.1-8.4. A good-quality aquarium test kit will help you monitor the pH level and ensure it remains within this range.

Water Hardness

Firefish do well in water with a hardness between 8-12 dKH (German degrees of hardness). Both soft and hard water extremes can cause health issues, so striking a balance is important.

Water Changes

Routine water changes are necessary to maintain a healthy environment for Firefish. Aim to change about 15-20% of the aquarium water weekly or bi-weekly. This helps to minimize harmful waste buildup and maintains optimal water quality. My Firefish seem to truly appreciate their freshly changed water, as they become more lively and active afterwards.

Remember, a healthy Firefish requires proper water quality. Keep closely monitoring temperature, pH, hardness, and routinely change the water to ensure your fish thrive.

Tank Maintenance

Firefish 2

When it comes to Firefish care, tank maintenance plays a crucial role. A clean and well-maintained tank promotes a healthy environment for your fish.

First things first, ensure that the tank size is appropriate. I remember when I started, I had a smaller tank which couldn’t support my Firefish’s requirements. A minimum of 20 gallons is needed to keep these fish comfortable and stress-free.

The water quality is vital. Invest in a quality water testing kit to check the pH, ammonia, nitrite, and nitrate levels. Firefish thrive in these parameters:

  • pH: 8.1 – 8.4
  • Temperature: 72°F – 78°F
  • Specific Gravity: 1.020 – 1.025

Incorporating a powerful filtration system is necessary to ensure consistent water circulation and cleanliness. This helps in maintaining the crucial water parameters mentioned earlier. Additionally, a protein skimmer is beneficial for reducing waste and maintaining clarity.

Regular water changes are key. Replace 10-15% of your tank’s water every week, or 20-25% every two weeks. This helps to remove impurities, which in turn, contributes to a healthier tank.

It’s important to maintain an adequate cleaning schedule. Remember to remove any algae build-up using a scraper or an algae eater species. Clean gravel and other decorative ornaments with a brush at least once a month.

By following these tank maintenance guidelines, your Firefish will have a cleaner, healthier, and happier home.

Tank Mates

Compatible Fish Species

When looking for tank mates for your Firefish, you’ll want to consider fish that will get along peacefully. I once had a pairing of Firefish and Purple Firefish, and they got along swimmingly. Some other compatible species include:

  • Clownfish: They are peaceful and can coexist comfortably with Firefish
  • Cardinalfish: They often stick to their own kind and don’t bother other fish
  • Blennies: These fish are generally non-aggressive

Remember that your tank’s size plays a significant role in compatibility. Ensure there’s ample space for all your fish to coexist peacefully.

Incompatible Fish Species

Avoid adding fish that are aggressive or known to bother their tank mates. Some incompatible species include:

  • Dottybacks: Their territorial nature may cause problems
  • Large Angelfish: They may consume smaller fish, including Firefish
  • Lionfish: These predatory fish might eat smaller fish in the tank

By choosing suitable tank mates for your Firefish, you’ll create a harmonious environment where all your aquarium inhabitants can thrive.


What To Feed

Firefish enjoy a varied diet. Their meals consist of frozen or live foods, such as:

  • Brine shrimp
  • Mysis shrimp
  • Copepods

Remember to include high-quality pellets or flakes as well. In my experience, my Firefish went crazy for live brine shrimp!


Feed your Firefish 2-3 times daily. Keep portions small to avoid overfeeding and to maintain a clean tank.

Time of DayFood Type
MorningLive or Frozen
MiddayPellets or Flakes
EveningLive or Frozen


  1. Variety is key for optimum Firefish health.
  2. Observe their eating habits to adjust portion sizes and food types accordingly.

During my time caring for Firefish, I noticed their preference for live foods and adjusted their diet to keep them engaged and healthy.

Common Diseases


As a Firefish owner, I have encountered a few common diseases that can affect these beautiful creatures. Some of the most prevalent diseases include:

  • Ichthyophthirius multifiliis (Ich)
  • Marine Velvet
  • Fin rot
  • Red Pest


Each of these diseases present distinct symptoms. Let’s have a look:

  • Ich: Small white spots on the body, erratic swimming, and flashing (scratching against surfaces)
  • Marine Velvet: Fine gold dust-like appearance on the fish, rapid breathing, and lethargy
  • Fin rot: Fading color, fraying or disintegrating fin edges
  • Red Pest: Reddish discoloration, loss of appetite, ulcers, and skin lesions


After identifying the disease, here are some treatments I recommend:

IchCopper-based medications, raising the temperature, and freshwater dips
Marine VelvetCopper-based medications, UV sterilizers, and quarantine
Fin rotAntibiotics (such as Erythromycin), water changes, and overall cleanliness
Red PestAntibiotics, salt baths, and maintaining good water quality


The best approach to keep your Firefish healthy is prevention. Some tips include:

  • Quarantine new additions before introducing them to the main tank
  • Regularly check water quality
  • Maintain proper water temperature
  • Feed them a balanced and varied diet
  • Provide them with a stress-free environment

Signs Of A Healthy Firefish

A healthy Firefish will have clear eyes and bright colors. Their fins should be free of damage and they should be actively swimming around their environment.

Appetite is key: In my experience, a healthy Firefish will display a strong appetite and eagerly accept the food offered to them.

Firefish are known for their inquisitive personalities. They should be seen regularly exploring their surroundings with curiosity.

It’s important to monitor the Firefish’s behavior closely. A sudden change in behavior, such as lethargy or hiding, could signal a potential issue.

Remember that a content Firefish will likely have a “favorite spot” that they’ll frequently return to. This is normal and not a cause for worry.

By keeping these signs in mind, you’ll better understand and care for your Firefish – ensuring they thrive in their environment.

Signs Your Fish Is Sick

One day, I noticed my Firefish acting strangely, and I knew something might be wrong. It’s important to pay attention to your fish’s behavior to catch any health issues early.

Loss of Appetite: A healthy Firefish should be eager to eat. If your fish isn’t eating, it could be a sign of illness.

Lethargy: A sick Firefish might be less active or seem disinterested in swimming around.

Changes in Appearance: Watch for physical changes, such as pale colors, cloudy eyes, or damaged fins.

I remember when my Firefish had white spots on its body, indicating a possible parasite infection. I acted fast and treated the tank right away.

Remember to keep an eye on your Firefish and stay attentive to any changes in behavior or appearance to ensure its health and happiness.



Breeding Setup

To create an optimal environment for breeding Firefish, I set up a separate tank with a sponge filter and heater. The breeding tank should have a temperature around 79°F (26°C) and plenty of hiding spots, like caves or PVC pipes.

How To Breed

I introduced healthy, mature Firefish (1 male, 2-3 females) into the breeding tank. They tended to spawn at night, laying adhesive eggs on a flat surface, such as a small piece of slate or a plant leaf.

Tips for encouraging breeding:

  • Provide a high-quality diet with a variety of foods
  • Maintain clean water conditions
  • Reduce stress by providing plenty of hiding spaces


After the eggs are laid, I removed the adult Firefish to prevent them from eating the eggs. The eggs should hatch in about 48 to 72 hours.

Post-hatching care:

  • Perform small, frequent water changes to maintain water quality
  • Feed the fry with infusoria or newly-hatched brine shrimp

In my experience, the fry grew quickly and were able to take crushed flakes and live foods within a few weeks. As they grew, I separated them by size to prevent larger siblings from eating smaller ones.

Product recommendations for Firefish:

  1. Tetra Whisper Bio-Bag Cartridge: These filter cartridges can help keep the water clean and clear in your Firefish tank.
  2. Seachem Prime: This water conditioner can help remove harmful chemicals from tap water and make it safe for your Firefish.
  3. API Aquarium Test Kit: Regular water testing is crucial for maintaining a healthy environment for your Firefish, and this test kit can help you monitor the levels of ammonia, nitrite, and nitrate in your tank.
  4. CaribSea Arag-Alive Bahamas Oolite Sand: This sand substrate is perfect for creating a natural-looking environment for your Firefish.
  5. Hikari Micro Pellets: These pellets are specially formulated for small tropical fish like Firefish and contain high levels of protein and other essential nutrients for healthy growth and vibrant coloration.
  6. Hydor Koralia Nano Aquarium Circulation Pump: This compact and efficient pump can help improve water circulation in your aquarium and provide your Firefish with a more natural environment.
  7. Zoo Med Laboratories AquaSun LED Aquarium Hood: This energy-efficient LED hood can provide ample lighting for your Firefish tank and help promote healthy plant growth.
  8. Coralife BioCube Protein Skimmer: This protein skimmer can help remove organic waste from the water and keep your Firefish tank clean and healthy.
  9. Omega One Freeze-Dried Krill: This tasty treat can provide your Firefish with a high-quality source of protein and help promote healthy growth and coloration.


Caring for Firefish can be both enjoyable and rewarding. I remember when I first started caring for these magnificent creatures, their vibrant colors and unique personalities quickly became a favorite in my aquarium.

Proper tank conditions are crucial. Maintain a suitable environment with stable temperature, good water quality, and plenty of hiding spots. Remember, they prefer a calmer and dimly lit space.

Feeding them a varied diet is key. Incorporate multiple types of high-quality foods to ensure they are receiving essential nutrients and minerals.

Keep in mind, they can be a bit shy. Give them time to acclimate to their new environment, and their fascinating personalities will shine.

With dedication and effort, these beautiful fish will thrive under your care, creating lasting memories and captivating moments that make keeping Firefish truly special.


What tank size is suitable for Firefish?
It’s best to house Firefish in a tank of at least 20 gallons. The larger the tank, the better!

What temperature should the tank be?
Maintain a temperature between 72°F and 78°F to ensure a healthy environment for your Firefish.

What to feed my Firefish?
Firefish are omnivores and enjoy a varied diet. Feed them a mix of high-quality pellets, flakes, and frozen or live foods.

What tank mates suit Firefish?
Firefish do well with peaceful, non-aggressive tank mates. Avoid housing them with larger or more aggressive species.

How to enhance Firefish’s color?
Providing a balanced diet, proper lighting, and a comfortable environment can help enhance your Firefish’s color.

Do Firefish require live rock?
Yes, including live rock in the tank is essential. It provides hiding places and contributes to a healthy aquarium ecosystem.

When I first got my Firefish, I was amazed at how shy it was. Over time, as it became more comfortable with the tank and its mates, it began to display more of its vibrant colors and unique swimming style. Don’t get discouraged if your Firefish seems timid at first; be patient and give it time to acclimate to its new environment.

Reference: Wikipedia.


Hi there! My name is Jacob, and I'm the founder of this Pet people blog that talks all about aquarium and fishkeeping. I've been passionate about fish and aquatic life since I was a kid, and I've spent countless hours learning about different species, their habitats, and how to create the perfect environment for them to thrive in.

Leave a Reply

Recent Posts