While betta fish are pretty easy to care for, they can sometimes grow unhealthy or catch diseases, causing them to get sick. To help you tell if your fish is sick or not, we asked several aquarium experts to explain the signs of an unhealthy betta. These experts also explained how to diagnose and treat common diseases affecting betta fish, as well as how to keep your fish happy and healthy. Read on to learn more!
Common Symptoms of Sick Betta Fish
Sick or unhealthy betta fish may show faded coloring, lethargy, and a refusal to eat. Signs of infections often include torn fins, white spots, cloudy eyes, and/or bulging eyes. A swollen stomach and raised scales can also be symptoms of the disease dropsy.
Steps
Diagnosing and Treating Fin/Tail Rot & Fungal Infections
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Look for deteriorating tails and fins to diagnose fin/tail rot. According to aquarium expert Marshall Stephens, the most common symptom of fin/tail rot is “deteriorated fins” or tails that have a shredded or torn appearance. He says there might also be “redness of the fins” and a “white cotton-like growth.” [15] X Expert Source Marshall Stephens
Aquarium Specialist Expert Interview. 3 January 2023.- Also, look for darker coloring near the end of the tail.
- Be aware that some longer-tailed varieties, such as halfmoon bettas, may try to bite their fins because they are too heavy. In this case, look for other symptoms of sickness as well as torn fins.
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Watch for white patches to diagnose a fungal infection . Stephens says the most common symptoms of a fungal infection are “cotton-like growths around the mouth and fins.” He says you might also notice “red streaks in the fins.” [16] X Expert Source Marshall Stephens
Aquarium Specialist Expert Interview. 3 January 2023. Your fish might also have clumpy fins or be less active than normal. [17] X Research source- While a fungal infection is different from fin/tail rot, they are treated in much the same way.
EXPERT TIPAquarium ExpertBrian Blake is an Aquarium Expert and the Owner of Boodleshire Aquatics based in the Kansas City Metro Area. With over 20 years of experience, Brian is an expert in freshwater planted aquariums, saltwater reef aquariums, and aquarium installation, care, and maintenance. Brian holds a Bachelor's degree in Ichthyology and Aquatic Environmental Science from Emporia State University.Look for multiple symptoms to properly diagnose a betta. A single symptom can be the result of several illnesses. For instance, white patches can be a sign of a fungal, bacterial, or parasitic infection. Noticing other bacterial infection symptoms, like cloudy eyes, might mean the patches aren’t fungal.
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Change the water to treat your fish. If you suspect your fish has an infection, Morton says the first step is to change out the water . [18] X Expert Source Craig Morton
Aquarium Specialist, Aquarium Doctor Inc. Expert Interview. 21 July 2020. Of course, you need to remove your fish and put it in a holding container while doing so. Fin/tail rot and fungal infections often develop from dirty water, so you need to provide a clean environment for your fish. Also clean the tank before putting fresh water back in. [19] X Research source- To remove the water in the tank, Morton suggests you use a hose to siphon out the dirty water. [20]
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Expert Source
Craig Morton
Aquarium Specialist, Aquarium Doctor Inc. Expert Interview. 21 July 2020. - Remove the decorations and gravel. St.Vil suggests soaking them in “1 part water and 3 parts vinegar” for 1 hour. Then, rinse them off thoroughly. [21]
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Expert Source
Cyriac St.Vil
Aquarium Expert Expert Interview. 7 March 2023.- For any rocks, bake them at 450 °F (232 °C) for 1 hour. Let them cool before adding them back to the tank.
- Clean out the tank with bleach and water. St.Vil recommends a solution of “1 part bleach and 5 parts water.” Then, rinse out the tank several times. [22]
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Expert Source
Cyriac St.Vil
Aquarium Expert Expert Interview. 7 March 2023. - Fill the tank with fresh water and add a water conditioner . Allow your fish to acclimate to the water before directly putting them back in the tank.
- To remove the water in the tank, Morton suggests you use a hose to siphon out the dirty water. [20]
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Expert Source
Craig Morton
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Add a medication into the water. To treat fin/tail rot , Morton suggests adding API BettaFix medication to the water. [23] X Expert Source Craig Morton
Aquarium Specialist, Aquarium Doctor Inc. Expert Interview. 21 July 2020. You can also give your betta ampicillin or tetracycline, which you add to the water. How much you add depends on the size of the tank—simply follow the directions on the package. [24] X Research source- If your betta just has a fungal infection , they won't need tetracycline or ampicillin. Instead, add a fungus eliminator to the water. This helps keep the fungus out of the water.
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Repeatedly change the water and add medication. Change the water at least every 3 days. Every time you change the water, add the medication back in. Only stop when your betta fish’s fins or tail seem to be growing back in, which can take up to a month. [25] X Research source
- For fungal infections , look for the white patches and other symptoms to disappear. When they do, treat the tank with BettaFix to help eliminate the fungus.
Diagnosing and Treating Velvet
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Look for a gold or rust-colored sheen on your fish. One of the best ways to diagnose velvet is to shine a flashlight directly on your fish. This will help you see the shimmer of gold or rust that this disease can produce on the scales. Your fish might exhibit other symptoms, such as lethargy, loss of appetite, clamped fins, and rubbing or scratching themselves against walls or items in the aquarium. [26] X Research source
- Velvet is a parasitic infection.
- This parasite can be prevented by adding aquarium salt
and water conditioner to your tank on a regular basis. [27]
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Research source
Add 1 tsp (6 g) of aquarium salt for every 2 ½ gallons (9 L) of water. You also need 1 drop of water conditioner per 1 gallon (3.8 L), though always read the instructions that come with your water conditioner.
- Only add extra salt when doing water changes, not when topping off a tank. [28] X Research source
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Separate the sick fish and use BettaFix to treat velvet. If your betta is in an aquarium with other fish, place your fish in a separate tank. Then, follow the directions on the bottle of BettaFix to add the correct amount to your fish’s water. [29] X Research source
- Alternatively, use a medication like Seachem Cupramine , Methylene Blue , or Maracide .
- Continue adding medicine until your fish no longer exhibits symptoms of velvet. Simply check the medication’s packaging to see how often to add it to the tank.
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Treat the whole tank with BettaFix to prevent velvet from spreading. If your betta lives with other fish, it’s a good idea to treat the entire tank for velvet. Velvet is a very contagious disease, so it could have spread to your other fish. Simply follow the directions on the bottle of BettaFix to add the correct amount to the community tank. [30] X Research source
Diagnosing and Treating Ich
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Look for white spots all over the body that look like salt. Ich is a parasite that produces small, white spots on your fish’s body, says St.Vil. [31] X Expert Source Cyriac St.Vil
Aquarium Expert Expert Interview. 7 March 2023. Also, look for clamped fins and lethargy. Your fish may also stop eating. [32] X Research source- Like velvet, this parasite is preventable if you treat the water right. St.Vil suggests doing “regular water changes and regular filter media changes” to prevent ich. [33]
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Expert Source
Cyriac St.Vil
Aquarium Expert Expert Interview. 7 March 2023. - Regularly adding aquarium salt or water conditioner to your tank can also help prevent ich. Always read the directions on the product to add the correct amount into your tank.
- Like velvet, this parasite is preventable if you treat the water right. St.Vil suggests doing “regular water changes and regular filter media changes” to prevent ich. [33]
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Expert Source
Cyriac St.Vil
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Raise the temperature to treat ich in large tanks. If you have a large community tank over 5 gallons (19 L), raising the temperature to 85°F (29°C) can kill off the parasite. Just don't do this if your tank is smaller, as increasing the temperature can overheat the tank and kill your fish. [34] X Research source
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Clean the tank and change the water. Ich thrives in dirty water, so it’s important to clean the water and tank. Siphon out the dirty water, disinfect the tank and decorations, and add in fresh, conditioned water. To help ensure the parasite is gone, heat the water to 85°F (29°C) before putting the fish back in the tank. [35] X Research source
- Be sure to treat the new water with water conditioner or aquarium salt before returning your fish to the tank. This helps keep the tank from reintroducing the parasite.
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Add an ich medication to the water, like Tetra Ick Guard . Ich medications kill off the parasite and help prevent other infections from forming. Simply follow the directions on the medication for the proper dosage and how often to add it. Some other common medications include API Super Ick Cure and Kordon Ich Attack . [36] X Research source
- BettaFix can also be used in a pinch.
Diagnosing and Treating Popeye
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Look for bulging eyes to diagnose popeye. Blake says “popeye is a symptom of a bacterial infection.” He says “when a fish becomes infected with bacteria in the eye,” oftentimes “the buildup of gas from the bacteria…results in the eye popping out.” So, look for either of your fish’s eyes to bulge or protrude from their head. [37] X Research source
- Blake notes that fish often develop popeye due to a weakened immune system, which might be “because of dirty tank water or improper water conditions,” like too cool or hot water. [38]
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Expert Source
Brian Blake
Aquarium Expert Expert Interview. 25 January 2024. - Popeye can sometimes be a symptom of other diseases, such as tuberculosis. Unfortunately, there is no cure for betta fish tuberculosis. [39] X Research source
- Blake notes that fish often develop popeye due to a weakened immune system, which might be “because of dirty tank water or improper water conditions,” like too cool or hot water. [38]
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Expert Source
Brian Blake
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Clean the tank and change the water. To treat popeye , siphon out the dirty water and sanitize the tank, decorations, and gravel. Then, add conditioner to some fresh water and pour it into the clean tank. [40] X Research source
- Continue to change out the water every 3 days until you notice your fish getting better.
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Add ampicillin into the water. Ampicillin helps treat popeye that’s caused by bacterial infections. Simply add this medication to the water every time you change the water—simply follow the directions on the bottle for how much to add. [41] X Research source
- Continue this regimen for 1 week after you stop seeing signs of the problem.
Diagnosing and Treating Dropsy
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Look for swelling and raised scales to diagnose dropsy. Dropsy is typically caused by an infection in your fish’s abdominal organs, which causes their belly to swell and bulge. This disease can also cause your fish’s scales to stick out, giving them the appearance of a pinecone. [42] X Research source
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Isolate your fish and add Epsom salt into the tank. Place your fish in a separate tank if they’re in a shared aquarium. Then, Morton recommends adding “2.5 teaspoons (12.5 g) of Epsom salt” for every “ten gallons (37.8 L)” of water in the tank to help cure dropsy. [43] X Expert Source Craig Morton
Aquarium Specialist, Aquarium Doctor Inc. Expert Interview. 21 July 2020.- Change the water every few days and add more salt until your fish starts to recover.
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Feed your fish antibacterial fish food. Morton also recommends feeding your fish antibacterial fish food to help cure dropsy. Replacing their regular food with food containing antibiotics can help kill off the bacterial or parasitic infection causing dropsy. [44] X Expert Source Craig Morton
Aquarium Specialist, Aquarium Doctor Inc. Expert Interview. 21 July 2020.
Diagnosing and Treating Swim Bladder Disease
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Look for sinking or an inability to swim to diagnose swim bladder. Swim bladder disease affects your betta fish’s swim bladder organ, which helps them float and swim properly. So, if they have this disease, you might notice them having trouble swimming upright, floating upside down, or sinking to the bottom of the tank. [45] X Research source
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Reduce feeding. Swim bladder disease is often caused by overfeeding. If your fish is eating normally (not refusing to eat or acting disinterested in food), skip feeding them for 1 day. This can help their digestive system reset and reduce the swelling causing swim bladder disease. [46] X Research source
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Change the water and add salt. Swim bladder disease can also be caused by a bacterial infection. So, it’s a good idea to siphon out the dirty water, clean the tank and decorations, and add in fresh, conditioned water. Morton also recommends adding “2 teaspoons (12 g) of non-iodized salt” and 2 teaspoons (12 g) of “Epsom salt per gallon (3.8 L) to the aquarium.” [47] X Expert Source Craig Morton
Aquarium Specialist, Aquarium Doctor Inc. Expert Interview. 21 July 2020.- If your betta fish is in a communal tank, place them in a separate tank for treatment.
Diagnosing and Treating Hole in the Head
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1Look for holes or pits around your fish’s head. Hole in the head disease results in holes and pits around your fish’s head and eyes. It can also cause your fish’s flesh to erode away. You might also notice your fish acting lethargic. [48] X Research source
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2Change and treat the water. Hole in the head can be caused by many things, but it's often due to a bacterial infection. So, siphon out the dirty water and replace it with fresh, conditioned water. Then, treat the water with a general medication that kills off bacteria and parasites, like API General Cure . [49] X Research source
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3Feed your fish high-quality food. Hole in the head can also be caused by nutritional deficiencies. Ensure your fish is getting all the vitamins and nutrients they need by giving them high quality betta fish pellets . [50] X Research source
Dealing with Constipation
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1Look for signs of swelling. If your betta fish suddenly swells, they may be constipated. It’s important to treat this problem soon. [51] X Research source
- Note: Constipation can look similar to swim bladder disease. If treating them for constipation does not help, follow the methods for curing swim bladder disease.
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2Stop feeding your fish for 1 whole day. The best way to help constipation is to stop your fish’s regular diet for 1 day. This will give them time to digest and move food through their system. [52] X Research source
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3Feed your fish live food after fasting them. For instance, feed your betta brine shrimp or blood worms. [53] X Research source According to Stephens, the general rule on how much food to give tropical fish, like bettas, is “not more than they can eat in about 30 seconds.” Make sure you feed your fish about twice per day. [54] X Expert Source Marshall Stephens
Aquarium Specialist Expert Interview. 3 January 2023.- Another great option is to feed your betta fish peas, as they contain fiber that can reduce constipation. Simply cut a few peas into tiny pieces.
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4Don't feed your fish as much. Constipation is generally a sign you are feeding your betta too much food. Therefore, once they start eating normally again, you need to feed them less than you were. [55] X Research source
Expert Q&A
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QuestionHow often should I change the water in the tank?Craig Morton is the CEO of Aquarium Doctor Inc. based in Huntington Beach California and servicing Orange County, Los Angeles County, and the Inland Empire. With over 30 years of aquarium experience, Craig specializes in creating custom aquarium designs along with aquarium installation, service, and maintenance.You should change 25 percent of the water in the tank every 2 weeks to keep your fish healthy.
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QuestionHow can I keep my betta fish warm?Craig Morton is the CEO of Aquarium Doctor Inc. based in Huntington Beach California and servicing Orange County, Los Angeles County, and the Inland Empire. With over 30 years of aquarium experience, Craig specializes in creating custom aquarium designs along with aquarium installation, service, and maintenance.I recommend using either a pad type heater for small fish bowls or a probe heater for larger aquariums.
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QuestionWhat medication can I use to treat fin rot?Craig Morton is the CEO of Aquarium Doctor Inc. based in Huntington Beach California and servicing Orange County, Los Angeles County, and the Inland Empire. With over 30 years of aquarium experience, Craig specializes in creating custom aquarium designs along with aquarium installation, service, and maintenance.API Bettafix is a medication you can buy in stores that will help cure fin rot.
Video
Tips
- Don't fret if your betta is changing colors. This is known as marbling and happens in most betta splendens. The only instances where changing colors may be a sign of sickness are when your fish fades or turns a paler shade of its previous color. This usually indicates that they are stressed or have a disease (like fin rot).Thanks
- Tears in the fins may be due to rough rocks in the tank or plastic plants, so remove these. Keep the water in the tank warm and clean and your Betta will heal itself.Thanks
- If a Betta is laying down a lot, this may be due to an infection or because they’re bored, unhappy, or hungry. Ensure your fish’s needs are being met before treating them with medication.Thanks
Tips from our Readers
- If you are unable to diagnose your betta's illness based on the visible symptoms, or if the disease resists standard treatments, an exotic fish veterinarian is your best resource. Veterinarians can identify more obscure diseases through laboratory testing, and also provide access to prescription medications not available over-the-counter.
- To prevent the spread of disease to your fish, always quarantine any new fish in a separate tank for several weeks before adding them to your main aquarium. Since some illnesses have long incubation periods without noticeable symptoms, quarantining lets you observe new fish for signs of disease. That protects your other fish.
- You should never treat your betta fish with disease medications without first properly diagnosing the specific illness. Bombarding fish with random antibiotic or antifungal treatments can be dangerous, or even counterproductive. It may also promote antibiotic-resistant superbugs.
- While dirty aquarium water easily spreads disease, do not overclean the tank by completely changing all the water and scrubbing too vigorously. That can remove helpful bacteria and crash the nitrogen cycle, further stressing your fish.
- Regularly test the water chemistry with liquid test kits instead of unreliable test strips. Improper pH, ammonia, nitrites or other imbalances stress fish and compromise immune systems, making them far more vulnerable to disease.
- Research all common betta fish diseases so you can recognize the symptoms early. The sooner you identify the illness, the faster you can start treatment, greatly improving recovery outcomes for your fish.
Warnings
- Beware of fish tuberculosis ( Mycobacterium marinum ). It is contagious and fatal in fish, and can be spread to humans. [63] X Trustworthy Source PubMed Central Journal archive from the U.S. National Institutes of Health Go to source Symptoms in fish include: Lethargy, popeye, and deformed skeleton/bent spine. Symptoms in humans: Large cyst-like red lump, usually where the bacteria entered (i.e., open cut). If you think you have fish TB, go to your doctor and specify that you own fish, or your doctor might misdiagnose you.Thanks
- Some "symptoms" aren't actually symptoms of a disease. For instance, lethargy can be caused by low temperature (no heater) and rips/tears in the fins can be from sharp objects. Don't just put in medication because one symptom of a disease is present! Look for other clues as well.Thanks
References
- ↑ http://www.earthsfriends.com/betta-fish-diseases/
- ↑ Craig Morton. Aquarium Specialist, Aquarium Doctor Inc.. Expert Interview. 21 July 2020.
- ↑ http://www.petful.com/misc/tips-for-raising-betta-fish/
- ↑ https://www.ouraquariumlife.com/fish/betta-fish-diseases/
- ↑ https://www.ouraquariumlife.com/fish/betta-fish-diseases/
- ↑ http://www.petful.com/misc/tips-for-raising-betta-fish/
- ↑ Wes Corbyn. Aquarium Expert. Expert Interview. 6 June 2023.
- ↑ Craig Morton. Aquarium Specialist, Aquarium Doctor Inc.. Expert Interview. 21 July 2020.
- ↑ http://www.earthsfriends.com/betta-fish-diseases/
- ↑ Cyriac St.Vil. Aquarium Expert. Expert Interview. 7 March 2023.
- ↑ http://www.earthsfriends.com/betta-fish-diseases/
- ↑ Craig Morton. Aquarium Specialist, Aquarium Doctor Inc.. Expert Interview. 21 July 2020.
- ↑ http://www.earthsfriends.com/betta-fish-diseases/
- ↑ http://www.earthsfriends.com/betta-fish-diseases/
- ↑ Marshall Stephens. Aquarium Specialist. Expert Interview. 3 January 2023.
- ↑ Marshall Stephens. Aquarium Specialist. Expert Interview. 3 January 2023.
- ↑ http://bettatalk.com/betta_diseases.htm
- ↑ Craig Morton. Aquarium Specialist, Aquarium Doctor Inc.. Expert Interview. 21 July 2020.
- ↑ http://www.earthsfriends.com/betta-fish-diseases/
- ↑ Craig Morton. Aquarium Specialist, Aquarium Doctor Inc.. Expert Interview. 21 July 2020.
- ↑ Cyriac St.Vil. Aquarium Expert. Expert Interview. 7 March 2023.
- ↑ Cyriac St.Vil. Aquarium Expert. Expert Interview. 7 March 2023.
- ↑ Craig Morton. Aquarium Specialist, Aquarium Doctor Inc.. Expert Interview. 21 July 2020.
- ↑ https://www.earthsfriends.com/betta-fish-diseases/
- ↑ http://bettatalk.com/betta_diseases.htm
- ↑ https://aquariumscience.org/index.php/10-2-3-velvet/
- ↑ http://www.earthsfriends.com/betta-fish-diseases/
- ↑ http://bettatalk.com/betta_diseases.htm
- ↑ https://www.earthsfriends.com/betta-fish-diseases/
- ↑ http://www.earthsfriends.com/betta-fish-diseases/
- ↑ Cyriac St.Vil. Aquarium Expert. Expert Interview. 7 March 2023.
- ↑ https://www.ouraquariumlife.com/fish/betta-fish-diseases/
- ↑ Cyriac St.Vil. Aquarium Expert. Expert Interview. 7 March 2023.
- ↑ http://www.earthsfriends.com/betta-fish-diseases/
- ↑ http://www.earthsfriends.com/betta-fish-diseases/
- ↑ https://www.ouraquariumlife.com/fish/betta-fish-diseases/
- ↑ http://bettatalk.com/betta_diseases.htm
- ↑ Brian Blake. Aquarium Expert. Expert Interview. 25 January 2024.
- ↑ https://www.ouraquariumlife.com/fish/betta-fish-diseases/
- ↑ http://www.earthsfriends.com/betta-fish-diseases/
- ↑ http://www.earthsfriends.com/betta-fish-diseases/
- ↑ https://aquariumscience.org/index.php/11-4-dropsy/
- ↑ Craig Morton. Aquarium Specialist, Aquarium Doctor Inc.. Expert Interview. 21 July 2020.
- ↑ Craig Morton. Aquarium Specialist, Aquarium Doctor Inc.. Expert Interview. 21 July 2020.
- ↑ https://aquariumscience.org/index.php/11-6-swim-bladder/
- ↑ https://www.ouraquariumlife.com/fish/betta-fish-diseases/
- ↑ Craig Morton. Aquarium Specialist, Aquarium Doctor Inc.. Expert Interview. 21 July 2020.
- ↑ https://aquariumscience.org/index.php/11-1-hole-in-the-head/
- ↑ https://www.ouraquariumlife.com/fish/betta-fish-diseases/
- ↑ https://www.ouraquariumlife.com/fish/betta-fish-diseases/
- ↑ https://japanesefightingfish.org/betta-fish-poop/
- ↑ https://japanesefightingfish.org/betta-fish-poop/
- ↑ https://japanesefightingfish.org/betta-fish-poop/
- ↑ Marshall Stephens. Aquarium Specialist. Expert Interview. 3 January 2023.
- ↑ http://www.petful.com/misc/tips-for-raising-betta-fish/
- ↑ Craig Morton. Aquarium Specialist, Aquarium Doctor Inc.. Expert Interview. 21 July 2020.
- ↑ Craig Morton. Aquarium Specialist, Aquarium Doctor Inc.. Expert Interview. 21 July 2020.
- ↑ Wes Corbyn. Aquarium Expert. Expert Interview. 6 June 2023.
- ↑ Craig Morton. Aquarium Specialist, Aquarium Doctor Inc.. Expert Interview. 21 July 2020.
- ↑ Craig Morton. Aquarium Specialist, Aquarium Doctor Inc.. Expert Interview. 21 July 2020.
- ↑ Wes Corbyn. Aquarium Expert. Expert Interview. 6 June 2023.
- ↑ Cyriac St.Vil. Aquarium Expert. Expert Interview. 7 March 2023.
- ↑ https://www.ncbi.nlm.nih.gov/books/NBK441883/
About This Article
To tell if a betta fish is sick, look for signs that it's unhealthy, like faded coloring, torn fins, bulging eyes, white spots, and raised scales. You should also watch out for a decrease in appetite or a low activity level, which are also signs that a betta fish is sick. Also, check your betta fish's stomach to see if it's swollen, which could mean it's constipated. If you think your betta fish is sick, it's important that you take action right away so it gets better. To learn more about treatment methods to help your betta fish feel better, keep reading!
Reader Success Stories
- "Thank you very much for sharing the information on this site. I found the site while looking for ways to both identify the sickness and treat my ill betta fish. I really like the clear, graphically well-designed page, and especially the illustrations. I am now following the directions given, and do hope to be able to cure my fish (apparently he has a fungal infection)." ..." more