Yellow patches on Julia Cories

[stephpartin]

Hello all and a happy holiday to everyone)

I have a 20 gal high tank with a Fluval HOB rated for a 70 gallon. All that is in the tank are 4 cories. Driftwood, plastic plants and other decorations are in the tank. The parameters are as follows: PH 7.4, Ammonia 0, Nitrite 0, Nitrate 10

My Julii cories have these yellow patches around their gills. I just noticed this yesterday and not sure how long they have been there because they hide quite often. Only one of them is acting sick by going off by himself and the black spot on his dorsal fin is fading. That is the only odd behavior so far. No rubbing or trying to scratch an itch.

Could it be ich or velvet? I attached a photo of the yellow looking growth on them. Any help would be greatly appreciated.

 

[V227]

Steph
Your pic evidently didn't post. As for the yellow patches on your Cory cats, likely not Ick, but could be Velvet / Oodinium. To be sure you might have to dim the aquarium light and shine a flashlight on the fish, checking for the speckled yellow parasitic coating on the body. If it is Velvet you should treat it with a copper based medication such as Cupramine or CopperSafe.
Try to post the pic again when you can.

 

[stephpartin]

Steph
Your pic evidently didn't post. As for the yellow patches on your Cory cats, likely not Ick, but could be Velvet / Oodinium. To be sure you might have to dim the aquarium light and shine a flashlight on the fish, checking for the speckled yellow parasitic coating on the body. If it is Velvet you should treat it with a copper based medication such as Cupramine or CopperSafe.
Try to post the pic again when you can.

Hello and thank you so much for your reply. I am attaching the photo that didn’t upload. I also sought advice from other fish communities and the overwhelming response is that the yellow patches are normal. Not sure how true that answer is but thought I would mention it. I will try dimming the lights as you suggested to look for speckles. Thanks again

 

[V227]

I don't think the yellow patches are typical, but it doesn't look like velvet. The patches might be a harmless genetic abnormally specific to a particular breeding operation. Velvet is a very fast acting parasite and would have covered and likely killed your catfish by now. The markings will give your catfish a little more character, separating them from the average ones.