Betta fish and internal parasites

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mariner
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Joined: Thu Oct 10, 2024 6:13 pm

Betta fish and internal parasites

Post by mariner »

I've noticed my betta has been acting sluggish and not eating much. His belly looks a bit swollen too. Could this be internal parasites? I've had him for about six months in a 5-gallon tank with a sponge filter, weekly water changes, and temp at 78F. He's usually super active, so this is weird.
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silverbreeze
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Re: Betta fish and internal parasites

Post by silverbreeze »

Sounds sketchy, mariner. Swollen belly and no appetite are classic signs of parasites. You might wanna try treating with metronidazole. I've had success with it before, but gotta be careful with dosing. What's your water change routine like? Sometimes poor water quality can mess with their immune system.
Foliums
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Joined: Thu Oct 10, 2024 7:09 pm

Re: Betta fish and internal parasites

Post by Foliums »

I agree with silverbreeze. Metronidazole is a solid choice. Also, check if his poop looks stringy or white. That's another giveaway. How often are you feeding him? Overfeeding can sometimes cause similar symptoms, but if it's parasites, you'll need to act fast.
vague
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Re: Betta fish and internal parasites

Post by vague »

silverbreeze wrote: Mon Aug 04, 2025 4:55 pm Sounds sketchy, mariner. Swollen belly and no appetite are classic signs of parasites. You might wanna try treating with metronidazole. I've had success with it before, but gotta be careful with dosing. What's your water change routine like? Sometimes poor water quality can mess with their immune system.
I'd second the metronidazole suggestion. Just make sure to follow the dosage instructions exactly. Also, keep the tank super clean during treatment.
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Aurora7
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Re: Betta fish and internal parasites

Post by Aurora7 »

My betta had similar issues last year. I used API General Cure and it worked well. How long has he been like this? If it's been more than a few days, I'd start treatment ASAP.
mariner
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Joined: Thu Oct 10, 2024 6:13 pm

Re: Betta fish and internal parasites

Post by mariner »

Thanks for the advice, everyone. I'll pick up some metronidazole today. His poop does look a bit off, so I'm leaning toward parasites. I'll also do a water change before starting treatment.
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silverbreeze
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Re: Betta fish and internal parasites

Post by silverbreeze »

Good call, mariner. Keep us posted on how he does. And yeah, clean water is key. Parasites thrive in dirty tanks, so stay on top of those water changes. You got this!
Foliums
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Re: Betta fish and internal parasites

Post by Foliums »

Aurora7 wrote: Mon Aug 04, 2025 10:56 pm My betta had similar issues last year. I used API General Cure and it worked well. How long has he been like this? If it's been more than a few days, I'd start treatment ASAP.
General Cure is another great option. It's a combo of metronidazole and praziquantel, so it covers a broader range of parasites. Just be sure to remove any carbon from your filter before treating.
vague
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Re: Betta fish and internal parasites

Post by vague »

Also, mariner, if you're using any meds, keep the lights off during treatment. Some meds can break down faster under light. And yeah, carbon will just soak up the meds, so ditch it for now.
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Aurora7
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Re: Betta fish and internal parasites

Post by Aurora7 »

How's your betta doing, mariner? Any improvement after starting treatment?
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