I have a 400 gallon rubber lined pool. I recently introduced goldfish that developed ich. I treated the water with seachem paraguard but they slowly d

[Mark Binder]

I treated an ich investation with paraguard but they slowly died off. The pond is now empty. What do I need to do to make it safe again for fish,

 

[Lisak1]

Welcome @Mark Binder ! Sorry that it's a problem with your fish that brought you here, but hopefully we can help you move forward.

You said your pond is 400 gallons. Do you have filtration? A waterfall or aeration? How old is the pond? How long was the pond up and running before you added the fish? I'm assuming these were the only fish in the pond. How many fish did you add? Are you sure it was ich? Did you take any photos of the fish or can you describe what you saw that made you believe it was ich?

Sorry for so many questions, but the more information you can share the better.

 

[Stephen Noble]

Welcome to the forum Mark Binder! It will greatly help if you take a few minutes to answer the questions posted by Lisak1. We are here to help.
Again, welcome!

 

[Mark Binder]

My pond is over 20 years old. It has a waterfall from a small pool above. I had several goldfish that had wintered over. I put 50 feeder goldfish in. After a few weeks I noticed most has white spots as they began dying off. I have a few potted plants. I know I should have quarantined those feeders

 

[Lisak1]

Yeah... quarantine would have been the way to go. Feeder fish are notorious for carrying diseases. And honestly, 50 fish is way too much for a 400 gallon pond. A half dozen would be just about right for your pond size, and they will soon turn themselves into a herd of 20 or 30.

Very pretty pond setting! I don't know much about ich or whether the pond is contaminated with it once the fish are gone. Some of the things I'm seeing on google suggest an aquarium needs to be fish free for 6 weeks to get rid of the parasite. I'd be tempted to empty the pond and let it sit dry for a few days and then refill it and try again - but that's just my know-nothing suggestion!

 

[cas]

Sorry to hear about your problem. I had a fish with ich years ago and did a lot of research. Here is what I found:

Ich is free-swimming until it attaches itself to the skin of a fish. The ich organism then forms a tough outer shell, or cyst, while it feeds on the fish’s bodily fluids. This encysted stage grows large enough to be seen with the naked eye and appears as a tiny white spot on the fish. After the cysts grow to a certain size, they break through the skin and drop off the fish and attach to any stationary object where they begin their reproductive stage. Then hundreds of free-swimming ich organisms can arise in less than a day and to re-infect the fish.

4 stages of Ich life cycle	How long each stage lives
Trophont-the parasitic stage on the fish	will mature and leave the fish after 3-7 days at 75-80 degrees
Protomont- parasite leaves the fish to encyst on the substrate to reproduce.	Will encyst within 24 hours, may be killed before it encysts.
Tomont- This is the reproductive and longest lived stage	can last up to 72 days (2 ½ months)
Theront- Free swimming looking for a host. This is when it can be killed.	At 86 degrees they will die within 24-48 hours with no host.

While ich is encysted on the fish or in their reproductive cyst, no medicine can affect it.
But once it’s free-swimming, it can be killed.
Since the life cycle of ich takes at least three days at 80 degrees to complete, ich must be treated for at least four days (at 80 degrees) or preferably for a week.
At colder temperatures the life cycle takes longer, so the treatment would need to be longer.
Life cycle is dependant on temperature: 4 days at 75 degrees, 8 weeks at 43 degrees, and can last as long as 72 days.
Most strains of ich can not reproduce in temperatures greater than 86 degrees. If the temps are consistently above 86 degrees for 10 days, ich may be eradicated.
In winter the parasite can exist in the cyst stage.

Now, since you don't have any fish, you don't have to worry about all the above. This is what I found recommended on this site years ago:
Do a 100% water change to the pond and add KMnO4 to the pond one time and all is done. The pond is clean.

 

[j.w]

@Mark Binder I agree wait and clear the pond of ICH and less fish and start out w/just a few and don't add too many more at a time and quarantine any new ones you add to the first group. You will have to let your pond cycle again before adding any fish as all that new fresh water will need time to get all the good bacteria growing in it again.