Clownfish Care Sheet

Clownfish care is beginner-friendly but requires proper tank setup, water quality, and diet to keep these popular saltwater fish healthy.

This care sheet outlines basic care needs for a variety of clownfish pet species, including: 

• Ocellaris clownfish
• Percula clownfish 
• Tomato clownfish 
• Clarkii clownfish 
• Maroon clownfish 
• Skunk clownfish 
• Spotcinctus clownfish 
• Cinnamon clownfish 
• Saddleback clownfish

Clownfish Species Overview

Clownfish are one of the most recognizable saltwater fish and are popular for their bright colors and beginner-friendly care requirements. 

While many people associate clownfish with orange-and-white coloration, they come in a wide range of colors and patterns. 

Clownfish are also known for their symbiotic relationship with sea anemones, though some species can be territorial, making careful tankmate selection important.

Clownfish Supply Checklist

Clownfish care requires essential equipment to maintain water quality and habitat stability.

• Appropriately sized aquarium 

• Appropriate food, dry and frozen 

• Décor 

• Water conditioner 

• Aquarium salt 

• Filter 

• Water test kit 

• Full-spectrum lighting 

• Net 

• Thermometer 

• Protein skimmer 

• Marine substrate 

• Heater 

• Refractometer 

• Live rock 

Clownfish Habitat

Choosing the Right Clownfish Tank Size

A single adult clownfish pet will need an aquarium that’s at least 29 gallons in capacity. Housing larger species or multiple fish will require a larger tank size.

Ideally, aquariums should be long, with a large bottom surface area (or “footprint”) so there's ample room for hiding spots and territories.

Because water conditions can change quickly in smaller tanks, always provide the largest habitat possible.

Place the aquarium in a quiet area of your home, away from direct sunlight, windows, and air conditioners.

Choosing Clownfish Tankmates

Carefully selecting compatible tankmates for clownfish is essential, as some species can be territorial or aggressive, especially toward other clownfish.

Some species may benefit from living alongside sea anemones, but compatibility should be researched before housing them together.

Clownfish are typically compatible with:

• Dwarf and large angelfish
• Blennies
• Gobies
• Hawkfish
• Pseudochromis
• Puffers
• Tangs
• Wrasses
• Hogfish
• Foxface (rabbitfish)
• Butterflyfish
• Basslets
• Anthias
• Dartfish
• Cardinalfish

Introduce new tankmates gradually and monitor the aquarium closely for signs of aggression or stress. If fish begin fighting, they should be separated to prevent injury.

Avoid overcrowding the aquarium, as excess stocking can increase stress, aggression, and disease risk. Because adding new fish can also affect water quality, monitor ammonia, nitrate, and pH levels closely after introduction.

Clownfish Filtration Requirements

Clownfish care requires a filtration system that maintains water quality and supports oxygen levels in the tank.

The filter should process all the water in the tank at least four times per hour.

For example, a 30-gallon tank should have a filter rated for at least 120 gallons per hour (GPH). If choosing between a 100 or 150 GPH filter, select the 150 GPH option.

Power (“hang-on-back”) filters and external canister filters are recommended because they provide mechanical, biological, and chemical filtration without taking up space inside the tank.

Clownfish prefer low to moderate water flow, so choose a filter with adjustable flow to maintain gentle circulation.

Clownfish Water Quality and Salinity

Clownfish care requires stable water quality and proper salinity to keep fish healthy.

Test your aquarium water regularly to ensure pH, ammonia, nitrate, and nitrite levels remain stable and within a safe range. Use an aquarium test kit to measure these parameters accurately.

As saltwater fish, clownfish require marine salt in their aquarium to survive.

When setting up the tank, gradually add marine salt until the water’s specific gravity reaches 1.020–1.025. Specific gravity should not change more than +/- 0.001 within a 24-hour period.

Use a hydrometer or refractometer to measure salinity and specific gravity accurately.

Clownfish Water Temperature

Clownfish are tropical fish that require stable water temperatures between 74 and 80 F to maintain health.

Use an aquarium heater to maintain this range and prevent fluctuations greater than +/- 2 F in a single day. Heaters should be paired with a thermostat to regulate temperature, though many modern heaters include built-in thermostats.

Heater wattage depends on tank size and room temperature. As a general rule, use 2.5–5 watts per gallon of water. For example, a 30-gallon tank requires a 75- to 150-watt heater.

Larger tanks over 50 gallons may need two heaters placed on opposite sides to prevent cold spots.

Check the aquarium’s temperature daily using a thermometer to ensure stability.

Decor and Accessories 

Clownfish care includes providing safe décor and accessories that support hiding, territory, and water quality

Substrate

Clownfish tanks should use a marine-safe substrate to support tank stability.

The bottom of the tank should be lined with 1–2 inches of sand or gravel suitable for marine environments.

Aquariums require about 1.5 pounds of substrate per gallon of water. For example, a 10-gallon tank needs about 15 pounds to create a 1–2 inch layer.

Always rinse the substrate thoroughly with clean water before adding it to the tank.

Hiding Places and Caves

Clownfish need hiding places such as caves, coral, or crevices to feel secure and establish territory.

Clownfish often hide or dart out to defend territory or capture food.

All décor should be rinsed thoroughly before being added to the aquarium.

Using Live Rock in Clownfish Tanks

Live rock provides both shelter and natural biological filtration in clownfish aquariums.

“Live” rock refers to the organisms living on the rock, not the rock itself. It contains beneficial bacteria and microscopic organisms that support water quality.

Live rock should be cured before adding it to the tank to remove decaying material that can raise ammonia levels.

Always wear gloves when handling live rock or performing tank maintenance.

Plants and Additional Decor

Plants and rocks can enhance the tank while providing additional hiding spaces.

Secure all plants firmly in the substrate to prevent them from toppling and injuring fish.

Protein Skimmer for Clownfish Tanks

Adding an appropriately sized protein skimmer to a pet clownfish’s tank can help support water quality and high dissolved oxygen levels within the aquarium.

Clownfish Cleaning and Maintenance

Clownfish care requires regular tank cleaning and partial water changes to maintain water quality and fish health.

Perform routine water changes of 10–25% every two to four weeks to maintain tank conditions. Avoid replacing all the water at once, as this removes beneficial bacteria that keep the ecosystem stable.

Most aquariums require a full cleaning about once a month, depending on stocking levels.

To clean a clownfish tank, follow these steps:

1. Wash your hands thoroughly and ensure there are no lotions, perfumes, or chemicals present. Do not remove fish from the tank, as this can cause stress or injury
2. Use a soft sponge or scrubber to clean the inside walls of the aquarium
3. Use acrylic-safe cleaning tools for acrylic tanks to prevent scratches, such as the API® Extra Long Algae Scraper for Acrylic Aquariums or API® Algae Pad for Acrylic Aquariums. 
4. Remove décor and artificial plants with heavy algae buildup
5. Scrub décor using an algae pad and hot water
6. If needed, soak décor in a diluted 3% bleach solution for 15 minutes, then rinse thoroughly until no odor remains and allow to air-dry completely
7. Inspect and clean the filter according to manufacturer instructions
8. Use a siphon vacuum to remove waste and debris from the substrate while draining water
9. Ensure all décor is fully dry and free of bleach odor before returning it to the tank
10. Add fresh, dechlorinated water that matches the tank’s temperature and salinity
11. Use only aquarium-safe cleaners on the exterior and avoid household cleaning products

Clownfish Diet and Nutrition

Clownfish require a balanced omnivorous diet with frequent, controlled feedings.

Clownfish should be fed small amounts two to three times per day. At each feeding, they should consume all food within one to two minutes. Remove any uneaten food daily to maintain water quality.

A balanced clownfish diet includes appropriately sized flakes, pellets, and frozen foods. Vary food types to ensure complete nutrition.

Frozen food should always be thawed before feeding.

Clownfish Care

Clownfish care requires consistent water changes, regular monitoring, and proper tank maintenance to keep fish healthy.

• Perform water changes of 10–25% every two to four weeks, or more often if needed.
• After adding new fish or equipment, test water quality weekly for at least two months to ensure pH, ammonia, nitrite, nitrate, carbonate, and hardness levels remain stable.
• If water parameters remain stable after two months, reduce testing to once per month.
• Replace water test kits yearly, as they expire over time.
• Monitor water levels and top off as needed with conditioned water that matches the tank’s temperature and salinity.
• Check water temperature, filtration, and equipment daily to ensure proper operation.
• Replace filter media monthly or rinse it in old tank water during water changes, depending on tank conditions.
• Do not use hot water, bleach, or chemicals when cleaning filter media, as this can kill beneficial bacteria.
• Avoid replacing all filtration media at once to preserve beneficial bacteria.
• Remove uneaten food daily using a fine-mesh net to maintain water quality.

Clownfish Veterinary Care and Health

Clownfish care includes monitoring health regularly and consulting a veterinarian when signs of illness appear.

In a properly maintained tank, veterinary care is usually only needed if a problem arises. However, newly introduced clownfish should be evaluated by a veterinarian within the first week to identify potential health issues.

Whenever possible, work with an aquatic veterinarian who can make house calls, as transport can be stressful for fish.

Signs of a Healthy Clownfish

• Bright coloration
• Full and symmetrical fin movement
• Intact fins with no discoloration
• Regular and active swimming pattern
• Strong appetite

When To Call a Vet for Your Clownfish

Contact a veterinarian if you notice any of the following:

• Lethargic or abnormal swimming (circling, listing, staying at the top or bottom)
• Receding fin edges with or without discoloration
• Decreased appetite for more than one day
• Itching or rubbing behavior
• Rapid breathing or flared gills
• Changes in gill color
• Lumps, bumps, or masses
• White growths or spots

Common Clownfish Health Problems

• Fin or tail rot
• Dropsy (fluid-filled body cavity)
• Parasites
• Bacterial infections
• Cancer
• Ich
• Pop eye
• Fungal infections (oral or skin)
• Swim bladder disorders