Sick Platy :(

[Nymerya]

My platy appears appears to be sick and I was looking for help. Context: he went through ich treatment successfully but I thought I saw a lesion on his gill after, so I treated him with API Fin & Body Cure. It did not appear to help but the lesion seemed small and I wasn't sure it was illness. Now he is showing other symptoms (about 2-3 weeks after the ich was eradicated) like gasping for air and clamped fins so I was hoping someone could provide some helpful info to help this little guy.

Tank size: 20 Gallon Hex
pH: 8.4
ammonia: 0 ppm
nitrite: 0ppm
nitrate: 10ppm
kH: unknown
gH: unknown
tank temp:

Fish Symptoms: Redish looking spot on gills, gasping for air at the surface, clamped fins, lethargic, not schooling/isolating himself

Volume and Frequency of water changes: 20% weekly

Chemical Additives or Media in your tank: API Stress Zyme

Tank inhabitants: 5 adult platys and 8 fry (in a breeder box)

Recent additions to your tank (living or decoration): 4 adult platys & 8 fry

Exposure to chemicals:
Previously treated him with API Fin & Body cure, Melafix, API Super Ich Cure

Picture of Gill Spot: (sorry about quality, he's camera shy)

 

[Nymerya]

I'm unable to change the original post but I forgot to include tank temp: 79F

 

[Colin_T]

Hi and welcome to the forum

Gasping for air at the surface, clamped fins, lethargic, not schooling/isolating himself can be poor water quality, gill flukes, external protozoan infection, or chemical poisoning.

The Ich treatment contains Malachite Green and should have killed any protozoans in the water so that is unlikely.
API Fin & Body cure contains salt and Doxycyline (anti-biotic) and will wipe out filter bacteria and most other bacteria on the fish.
Melafix doesn't do much.

The fish doesn't look too bad in the picture but it's a bit hard to tell due the angle. I can't see much when I turn my head 90 degrees

If the water quality is good then it is probably stress from all the medications you used. At this stage you could try doing a 75% water change and gravel clean the substrate each day for a week and see how the fish goes. After that do a 75% water change and gravel clean the substrate each week.

If you can post a short 20 second video clearly showing him gasping at the surface we might have more to go on. But if he's eating then I would just do water changes and see how he goes.

Are the other fish ok?