Cardinal Tetra Unusual Parasite Help ID!

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Aquarium Advice Newbie
Feb 19, 2023

In my planted 50 gallon, one in a school of 8 cardinal tetras developed a rather unusual white spot his side that had several protruding hairs that could be seen to drift along as he swam. He began swimming listlessly and often tipping nose down and just catching on the plants and resting. He will swim for some time in the school but tires very quickly. So, I caught him with the net and took some pictures. To get a closer look at what it might be, I gently tweezed this strange white thing and it just popped out. I would be fascinated to know what this is? I haven't manage to find it yet looking up various possible parasites and diseases.

I stained the slide to better see form under the microscope. Size: 1 mm
40x magnification

1~ Cardinal Tetra has large white spot protruding from the side of his body.
2~ (ammonia - 0, nitrites - 0 , nitrates 5ppm, temp - 79F, pH 6.8)
3~ 50 gallon, six months old
4~ Fluval 407 Canister Filter GPH: 383
5~ 10 mollies, 8 cardinal tetra, 5 Kuhli loaches, 3 mystery snails. Mollies 2 inches ranging to babies, , cardinal tetra about 1 inch each, Kuhlis are around 1.5 inches long (quite young)
6~ 30% water change and gravel/sand vacuumed one week ago. Water change every two weeks 25%. Gravel cleaned once every three weeks.
7~All fish have been in tank for 6 months.
8~Tank is heavily planted, led full spectrum lights, high tannin level in water from driftwood.
9~ Fish are fed twice daily, mornings they get Fluval high protein bug bites/Fluval colour enhancing flakes, evenings they get brine shrimp and some live moina and copepods. Moina and copepods are bred by me at home. Three cultures going.


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Thanks for the reply! The fish is doing okay today so I'm hoping he makes it. I'll look into your suggestions! Definitely possible!
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