Is your betta fish looking bloated or abnormally round around the belly? A swollen stomach in bettas isn’t just a cosmetic issue—it can signal serious internal problems like constipation, dropsy, or internal parasites. If you’re serious about improving water quality and long-term betta health, download Aquaponics 4 You to learn how to create a balanced system that reduces stress, prevents disease, and keeps your fish naturally healthy.
What Does a Swollen Stomach Look Like in a Betta?
A betta with a swollen stomach will typically have a distended, round belly that sticks out to the sides. The swelling may appear suddenly or gradually over several days. Depending on the cause, the betta may also show signs like:
- Loss of appetite
- Lethargy or floating near the surface
- Clamped fins
- Swimming problems (difficulty diving or staying upright)
- Raised scales (a pinecone appearance, in the case of dropsy)
Main Causes of Swollen Stomach in Betta Fish
The causes range from mild (like overfeeding) to potentially fatal (like dropsy). Here’s how to tell the difference:
1. Constipation
- Common cause of swelling in bettas
- Triggered by overfeeding or low-fiber diets (too many pellets or freeze-dried foods)
- Symptoms: Bloated belly, no feces, lethargy
2. Dropsy
- Life-threatening bacterial infection causing fluid buildup
- Scales stick out like a pinecone due to internal swelling
- Fish may float or lie at the bottom, usually won’t eat
3. Overfeeding
- Feeding too much or too often stretches the digestive system
- Especially risky when feeding freeze-dried food without soaking
4. Egg Binding (in Females)
- Female bettas may swell when full of eggs
- If unable to release them, the eggs may build up and cause swelling
- Not usually dangerous unless persistent
5. Internal Parasites
- Protozoa or worms can bloat the digestive system
- May cause stringy white feces, lack of appetite, or weight loss with a bloated belly
6. Tumors or Organ Failure
- Less common, but possible especially in older bettas
- Growths or kidney failure can cause internal swelling and should be diagnosed by exclusion
Mid-Article CTA: Want a Natural Way to Keep Bettas Healthy?
Fish health starts with water quality and balance. Learn how to create a low-stress, self-cleaning environment where bettas thrive naturally. Aquaponics 4 You shows you how to use plants and fish in harmony—reducing bloating, water issues, and disease outbreaks.
How to Treat a Swollen Stomach in Betta Fish
1. Identify the Cause
Before treating, observe your betta’s behavior and symptoms closely. Are the scales raised? Is the betta pooping? Is it male or female? This determines your treatment path.
2. Treating Constipation
- Fast your betta for 1–2 days (no food at all)
- Feed a blanched pea (skin removed) on day 3 to stimulate the digestive system
- Maintain clean, warm water (78–80°F)
- Avoid freeze-dried foods during treatment
3. Treating Dropsy
Dropsy is more serious and requires aggressive treatment:
- Move the fish to a quarantine tank with clean, warm water
- Use antibacterial medications like Kanaplex or Maracyn 2
- Add aquarium salt (1 tsp per gallon) to reduce fluid retention
- Increase oxygen via air stone and keep water pristine
Unfortunately, dropsy often has a poor prognosis if not caught early.
4. Treating Parasites
- Look for signs like weight loss despite swelling, white feces
- Treat with antiparasitics such as API General Cure or Seachem Metroplex
- Feed medicated food if your betta is still eating
5. If Female Is Egg Bound
- Maintain optimal water temperature (78–80°F)
- Add hiding spots and gentle stimulation with a mirror (temporarily) to encourage egg laying
- Separate from males if stressed
6. Tumor or Organ Failure
If the swelling doesn’t respond to any treatment and the betta is still eating, monitor comfort and water quality. Sadly, there’s no cure for internal tumors or organ failure—supportive care is your best option.
Preventing Swollen Stomach in Bettas
Feed a Balanced Diet
- High-quality pellets (e.g., Omega One, Fluval Bug Bites)
- Frozen or live foods like daphnia or bloodworms for fiber
- Soak freeze-dried foods before feeding
- Feed 2–3 small meals a day, not one large one
Maintain Clean Water
- Perform regular water changes (25–30% weekly)
- Keep ammonia and nitrites at 0 ppm, nitrates under 20 ppm
- Use a sponge or gentle filter to reduce stress
Watch Temperature
Keep water between 78°F and 80°F. Cold water slows digestion and increases the risk of constipation and infections.
Use Live Plants
- Java fern, Anubias, Hornwort, or floating plants add oxygen and reduce stress
- Plants help reduce harmful waste and offer hiding spots
When to See a Vet (or Euthanize)
If your betta shows signs of suffering (unable to swim, not eating for 7+ days, struggling to breathe, extreme swelling), humane euthanasia with clove oil may be considered. A vet who specializes in aquatic animals can help confirm your diagnosis and provide guidance.
Quick Symptom & Diagnosis Guide
| Symptom | Likely Cause | Suggested Treatment |
|---|---|---|
| Bloated, no poop | Constipation | Fasting, pea feeding |
| Swollen with raised scales | Dropsy | Antibiotics, salt bath |
| Swollen, white stringy poop | Parasites | Metroplex, General Cure |
| Swollen, female, no eggs | Egg bound | Warm water, mirror trigger |
| Chronic swelling, older betta | Tumor or organ failure | Monitor, supportive care |
Final CTA: Build a Tank That Supports Long-Term Betta Health
Betta fish deserve more than just clean water—they thrive in natural, balanced environments. With Aquaponics 4 You, you can create a betta tank that supports digestion, reduces stress, and prevents bloating naturally—by using live plants and biofiltration that keeps the water perfect. Download the guide and start your journey to better betta care today.