Goldfish Disease Treatment

[coral49]

Hello - Looking for help on a sick fish bloody tail from last week, now with a bloody gill cover and tail

Pond is 1000 gallons - only goldfish (~12) most are full size, on the 6th season with no issues till now. In Chicago area and the weather just started cooling off pond water around 65.

Water parameters are all good using API Pond Master Kit - About once a month I do 25% water change with sponge rinse in canister with UV. It is a hard scape pond can't bog.
pH 7.0
Am - 0
nitrite - 0
phosphate - just a touch

When I saw the tail - did another 25% water change and it is getting worse after a week.
Can you please help with disease and treatment.
thank you

 

[WaterGardener]

Do you have a test for KH? if not, please get one and post the results here.

The pH is on the border of being too low. I would raise that by adding baking soda. Lots of info if you search the forums for that or anywhere online.

If you want to medicate the pond, I would use FMG, formalin and malachite green. Be sure there is no salt in the pond if you use it and make sure the dosage is correct for your pond. It's a 3 day treatment, with water changes before each treatment. It is sold under several different names and brands, but will easily show up when searching FMG for ponds.

Good luck with your fish

 

[Lisak1]

This is definitely a water quality issue. You can treat the fish, but you need to figure out what the problem is.