Mitz74 Mitz74
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  • Posted on: 25/2 19:12
Dwarf Rainbowfish tumour, fungus or parasite? #1
Hi all,

I have a male dwarf/neon rainbow fish with a strange growth. It started on the base of his left pectoral fin initially but is now getting bigger and moving to the gills.

I recently lost the female as she had a similar growth in her gills and could not eat.

I have treated with anti internal bacteria and anti fluke (praziquantel), salt baths and tried to take off the growth with sterile tweezers (thought it may have been an anchor worm) to no avail. He is still eating as usual and is in quarantine.

Any help to save my little fishy would be greatly appreciated. 🙏

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Fishlady Fishlady
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  • Posted on: 25/2 19:56
Re: Dwarf Rainbowfish tumour, fungus or parasite? #2
I think he has lymphocystis which is a viral infection and unfortunately untreatable. It's usually not fatal, but in cases where it infects the gills, death is more likely. Sorry I couldn't offer better news
Mitz74 Mitz74
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  • Posted on: 26/2 21:57
Re: Dwarf Rainbowfish tumour, fungus or parasite? #3
Oh no. I assume other fish can catch this infection as it arrived on a german ram which later died (pets at home). It was quarantined after 24 hours but i guess it was too late :/
Fishlady Fishlady
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  • Posted on: 28/2 12:21
Re: Dwarf Rainbowfish tumour, fungus or parasite? #4
It's not extremely contagious so most may be unaffected. To help the other fish maintain immunity make sure the tank is kept very clean and that you do regular partial water changes.
Mitz74 Mitz74
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  • Posted on: 7/3 8:47
Re: Dwarf Rainbowfish tumour, fungus or parasite? #5
The growth just got bigger and bigger so I let him go. Thank you Fishlady for your help.
Fishlady Fishlady
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  • Posted on: 7/3 10:04
Re: Dwarf Rainbowfish tumour, fungus or parasite? #6
Sorry to hear that. It's never an easy decision to make, but sometimes it's for the best and the right thing to do for the fish