Oscar not eat and Losing scales

[Isaiah75]

Have you tested your water?

Yes

If yes, what is your ammonia?

0ppm

If yes, what is your nitrite?

0ppm

If yes, what is your nitrate?

40ppm

If I did not test my water...

...I recognize that I will likely be asked to do a test, and that water tests are critical for solving freshwater health problems.

Do you do water changes?

Yes

What percentage of water do you change?

51-60%

How frequently do you change your water?

Every week

If I do not change my water...

...I recognize that I will likely be recommended to do a water change, and water changes are critical for preventing future freshwater health problems.

My Albino Oscar stopped eating a couple days ago and is now losing scales. I need help identifying the issue so I can save him. He’s been sitting in the bottom with semi labored breathing. I did a large water change (~75%) two days ago. I typically do a 50-60% weekly. I had just checked the water parameters and they all are where they typically sit for this tank. I added aquarium salt and PraziPro to the tank yesterday. He’s in a 150g tank w another Oscar and a few plecos. Please let me know if there’s anything I can do. I’ve attached photos for help in diagnosis. Thank you I’m advance.

 

[MultipleTankSyndrome]

40 ppm NO3 is probably the cause. You'd ideally want to keep it at 5-10 ppm max.

duanes can give you a very good explanation.

 

[aroijuana]

Looks like dropsy without bloating or one of your plecos is going to town on him. I'd use a kanaplex treatment just to be sure & keep a close eye at night.

 

[duanes]

To me it looks like a bacterial infection brought on by the chronic effects of high nitrate.
Although a 50% water change once per week may have been sufficient when the oscar was small, now that it has grown and is producing twice as much waste, that routine is not enough.
Permanently doubling or tripling the volume and frequency of water changes to cut nitrate by 2/3 would be my solution.
Although an antibacterial med would be great to treat the immediate infection, unless you mitigate the initial cause of the problem (nitrate) I doubt meds will be a permanent solution.

 

[Randles]

Need to reduce to nitrate asap. Maybe instead of 50% once a week up this to twice maybe even three times per week. Personally I would do this sooner rather than later. Good luck, I'm sure he'll make a recovery if you follow the advise here.

 

[MultipleTankSyndrome]

FYI, if the NO3 was 40 ppm even after that 75% water replacement, you may have to reduce the stocking.