Sick fiah

[mcgregorphoto]

Hi,
I have a 20k gallon pond with a bog filter in NY. We have a couple dozen goldfish that are between 2 and 4 years old. We recently had a fish get sick, see attached. My question; does this look like fungus or columnaris maybe? My biggest question is; do I need to do something urgently to keep this from spreading? Catching a 5” fish in a pond this size seams like a Herculean task. I appreciate your help.
Best,
Mike

 

[Tula]

I can't tell with certainty but it looks like a fungus. Is the fish in otherwise good condition, no tattered fins, redness or pine coned scales? Is the fishes behavior normal, eating and swimming normally?

Honestly catching him to provide treatment could be very difficult in a pond of that size. If you feed them in a certain area maybe another person could help with a net?

 

[Meadowlark]

Howdy @mcgregorphoto

I can't diagnose from the photo sorry. If you could describe the symptoms, perhaps we could give a better response. If it is bacterial, you usually see lethargy, ulcers, red streaks.

Water quality is the #1 cause of health issues in goldfish. Check for ammonia or nitrate above 0 ppm. Has there been recent sudden temp. changes? Or possibly low oxygen?

If any of these are indicative, water change would be in order.

 

[mcgregorphoto]

I can't tell with certainty but it looks like a fungus. Is the fish in otherwise good condition, no tattered fins, redness or pine coned scales? Is the fishes behavior normal, eating and swimming normally?

Honestly catching him to provide treatment could be very difficult in a pond of that size. If you feed them in a certain area maybe another person could help with a net?

He swims well and eats. If he was lethargic he would be easier to catch!

 

[mcgregorphoto]

Thanks, I’ll check ammonia and nitrate levels. Temp has been steady and oxygen should be plentiful. The water has been a little murky so we just added some barley extract. We also got some water lettuce from another pond nearby. Those two things are the only obvious differences I can think of. That said, I’ll report back with some water quality numbers. Thanks for the help.