Can potassium permanganate be used to euthanize ALL fish in a pond??

[Sarasa]

I have had ornamental ponds for 20 years. I had a nearly 10k koi pond but I had a catastrophic winter kill about 6 years ago, so I reduced the pond depth to 2' and kept waterlilies and sarasa comets. I am moving and the new owners have preschool kids and do not want the pond. I must empty and fill it in quickly. People have taken the lilies and the best and biggest of the sarasa comets but there remain perhaps 75 unwanted, unattractive mongrel sarasas from babies to 7" that have regressed through inbreeding to the carp/comet norm (short fins, loss of coloration). Fish stores do not want them; not even a supposed fish rescue group is interested. Euthanasia is the only humane option at this point. Individual Oil of clove is not an option for this many fish.

I have a large supply of potassium permanganate that I used on occasion to clean the pond from when I had koi. Would a strong overdose of this be a swift, humane method of dispatch? I know potassium permanganate will kill them, I'd just like it to be fast so there is no suffering.

 

[j.w]

@Sarasa
I couldn't do it and have no response other than I would run an ad on for free on Facebook, Craigslist or Nextdoor.com. There is always someone who will want them to start a new pond. Even just post a sign on a pole in your area, free pond fish. Some vets offices, have bulletin boards where you can post. Maybe even ask a pet store if you can put a flyer outside their store. Grocery stores may have a board also.

 

[Marck]

Was your removal of the pond a condition of the sale? I suppose it is better to do it yourself than leave it to others.

Odd a self-professed 'fish rescue group' won't take them. Perhaps they only want to rescue expensive fish...

Of course, fish are food. Perhaps you can drain the pond to down to a few inches and let the raccoons have a feast. I wouldn't find that inhumane. That is how wildlife hunt.

 

[Sarasa]

The pond must be removed and filled by Friday. The bald eagles and raccoons have been eating them for more than a decade. But with the time constraint, I need a more efficient method.

I know this isn't ideal. When one keeps very prolific comets (each female breeds every 14 days!) a responsible fish keeper has to cull annually or the health of all the fish suffer - an artificial pond's filtration can only handle so much fish load and there are few predators in an ornamental pond as there would be in a natural pond. I have been unable to do this unpleasant but essential task for the last two years due to illness which is why I now have so many ugly, unwanted fish.

BTW live animals are not permitted to be listed on Marketplace or Craigs List. But the people who would show up for these greenish or transparent whitish comets will be using them as feeder fish. So they'd have to suffer the trauma of being caught, transported and eaten by someone's reptile.

(I think the fish rescue group only wants to accept fish they think they can resell and use their "fish rescue" angle to get free media coverage.)

 

[Mmathis]

I tend to agree with @j.w, and as far as whether PP will work or not — I have no idea, but not knowing would make me want to search even harder. Maybe check with a local veterinarian and see if they know or can offer other options. Please don’t release them into local waterways.

 

[GBBUDD]

Catch them put them into a zip lock bag and place them in the freezer . As the temp drops like in winter they will slow down and go to sleep as the temp drops further so does the heart and they never awaken

 

[mrsclem]

I just used PP to kill off a bad snail issue in a plant only pond. The chemical is safe for fish at low levels but can kill. How humanely? Damage to gills? It could take days or longer. Drain the pond , put the fish into large containers and freeze.

 

[mrsclem]

You still may want to consider Craigslist, advertise free fish, must take all. Even if for feeders, at least they would have a chance

 

[Nevermore44]

If you can’t get any takers read up and get oil of cloves.

 

[GBBUDD]

Why poison them put them in the freezer let the slowly go to sleep just like a winter cycle but they never wake

 

[WaterGardener]

I would catch them and put them in buckets or tubs and use clove oil. I've had to do this with about 50 young fish. It was difficult, but there was no other alternative. If you are filling in the pond, you will need to drain it anyway, so that would make catching them easier.

Sorry you have to do this. It's not a pleasant task and it still haunts me.

 

[poconojoe]

It's strange that no one wants them.
They are at least good feeder fish for someone that has turtles, oscars or other carnivorous pets.