Method to remove leeches from a pond

[OttawaReefer]

We moved into our house in September and there was a pond already built in the backyard.  The previous owners didn't take care of it at all and it was basically a swamp pit when we got the house.

This spring I have replaced the pump with a 4000gph pump (the previous one didn't work at all) and emptied the pond, removed all the large rocks that had fallen into it and refilled the pond.  It's had the water running for just about a month and a bit now.  I put some koi in the pond last week.  They were doing fine, mostly hunkered down in the deepest part of the pond and we saw them swimming about sometimes.  Today all three were dead.  When I went to remove them each body was covered in leeches.  Leeches on them, in the gills, and when I scooped them there were about fifty left in the skimming net alone.

I can't say with any certainty that it was this plague of leeches that killed the fish, but I can't rule it out either.  Most of the leeches were about a centimeter to a centimeter-and-a-half in length and dark brown.  It was the quantity of them that was surprising.

Before adding any other fish I would like to treat the pond to ensure that the leeches are gone.  What would be a good product to treat a pond for leeches?

[dan2x38]

Hey Big Al's is hosting a Pond demo this Sat. The speaker is suppose be renowned.

http://ovas.ca/index.php?topic=44515.0;topicseen

[JetJumper]

Pond Salt?  Might possibly work.

[OttawaReefer]

I thought that salt would harm the plants in the pond

[dan2x38]

I thought that salt would harm the plants in the pond

I wouldn't use salt it will harm the plants! Plus anything you put in a pond I would believe would stay there a long time. Here is acrazy idea!  Put a piece if red meat near where you know there a leaches. Leave it for a bit then pull it out see if they attached to it. Like I said just a thought.

I found this article I was interested - "http://blog.thepondguy.com/2008/06/23/controlling-leeches-pond-lake-q-a-week-of-may-16th/". There were some other interesting links I didn't read too. I Googled, "remove leaches form ponds".

[Brent Shaver]

When I was working in the golf industry in the TO area we had ponds everywhere as everyone knows.  We would get over run by leeches as well.

One method we used (ONLY IF THAT IS ALL THAT IS LIVING IN POND) was we bought although I am sure it could be borrowed for the short term use you would need is, we put stakes around the pond and ran fencing wire (submerged) from stake to stake and hooked it up to an electric fence machine.  Although not fatal to humans it does kill any living item in the water.  If you have ever been on a farm and got to close to one of these fences it is a nice wake up.

The reason we used this method is because of envormental issues.  As this will kill the leeches for sure it doesnt contaminate the soil or water once done.  Our pond held 300 thousand gallons for irrigation and we would run this once every year for a half day.  Most home ponds would only need a couple hours if that due to water volume.

It is just a suggestion and a sure cure.

DO NOT USE AN EXTENTION CORD TO BLOW A BREAKER!!! As a cheat..

[JetJumper]

DO NOT USE AN EXTENTION CORD TO BLOW A BREAKER!!! As a cheat..

Took away all my fun.

Time for plan B

[QueensU]

hell of a security system.

Are there any pond fish that eat leaches?

[Fishnut]

Wicked idea...zap the leaches!!   I'm not too sure that's the safest method if you have kids or pets around but it sounds fun   I was about to zap the raccoons that visited my pond but they didn't come back last year.

I would make a few calls to some pond experts.  I've had some really bad luck with the local pond "experts" but there's a pond/koi place in Toronto that I've been recommending to a lot of people on this forum...http://www.clarkekoi.com/HomePage.html.  So far, they have given me THE BEST information about ponds and koi.  They'll be able to tell you how the slugs can be removed. 

Googleing can be very informative, but anyone can put anything on-line these days so it's not necessarily accurate, which is why I try to rely on experts and published material...books and magazines. 

That pond seminar might be interesting.  It's being done by a Tetra Sales Rep though, so I hope it's not just going to be one long sales pitch for Tetra products.  The last time I went to a "seminar", that's all it was...not Tetra though.  The guy didn't have a clue about the subject outside of his line of products and what they were used for.

[dan2x38]

hell of a security system.

Are there any pond fish that eat leaches?

An article I read said sun fish (perch) & bass. There are several that would survie in a pond depending on the size, aeration and population.

[OttawaReefer]

We're not allow to "keep" native sport fish. 

I'm wondering if those de-worming tablets/powder you can get for pets/fish would work.

I couldn't believe the number of them that were all over the fish. 

[dan2x38]

Wow that sounds nasty!!! I would be POed. Maybe the person presenting at the Big Al's pond demo can help? One article mentioned making a trap with a coffee can and adding meat to it, chicken liver, etc. They made holes in the can with jagged edges on the inside by using a nail. Then add a rock inside it. I would also add a sting or wire to the can so I could easily pull it out.

They mentioned a product that gets rid of the muck build up the leaches live in. Sounds like a common problem I never heard of it before but very nasty problem. Please update the out come this is interesting all the same.

There is a pond club locally and I think they have a forum. I believe the member here that helps organize there is 'PondBoy'. Maybe going on the forum http://www.thegab.org which is a dedicated Goldfish board there would be some folks with more experience with this issue. I've always heard good things about that site.

[JetJumper]

There is a pond club locally and I think they have a forum. I believe the member here that helps organize there is 'PondBoy'. Maybe going on the forum http://www.thegab.org which is a dedicated Goldfish board there would be some folks with more experience with this issue. I've always heard good things about that site.

The Pond Boy's site can be found here.
http://thepondboy.com/

His name is Greg.  Seems to be a pretty knowledgeable guy.  Try giving him a call and see what he has to say.

[Fishnut]

I'm glad you know that we're not supposed to keep native fish in captivity .  So I've been doing some reading on leeches this afternoon.  What I found odd was that leeches were found in a closed pond....not attached to a native stream, river or creek.  I found out that leeches don't need males and females because they produce their own fertile eggs.  All you need is one leech .  They lay them on any surface beneath the water...rocks, liner, plants, everything.  It wouldn't surprise me in the least if the came in as eggs on a plant from somewhere and have been living in the muck of the pond.  In addition to blood, they eat dead or decaying organic matter, so they must have been having a blast in the pond before you cleaned it and it might explain why there were so many on the dead fish.  In theory, the meat method might work...just make sure you don't wait too long before dragging it back out.  Once leeches are full, they drop off their host.

So in treating your pond via whatever method you choose, you may have to think about repeated doses.  Will the meds affect the eggs?  If not, will you be 100% sure you've zapped/chemically killed the newly hatched leeches before they had a chance to lay more eggs? I still haven't seen any consistent method for getting rid of them though.  Some say the meat method works, other say it doesn't.  I did read, however that if you decide to use chemicals, you need to take precautions so the wildlife that visits your pond won't be harmed.

What about draining the pond completely and letting it sit dry?  I doubt leeches would be able to survive that...not sure about the eggs though .  You've taken out all the rocks already, that's great.  If you also take out and get rid of the plants, that means you have eliminated most of the places where leeches like to lay eggs.


Net a few out of the pond to do experiments on them .

When you find some definitive answers, I would love to know what's working for you.

[limmer]

Why don't you see it a bait store will buy them off you.
Bass really love them.

[Cbellehumeur]

I like the Zapping method...+1 for me

[ciaus]

Having grown up in northern BC, where all bodies of water have leeches, I have heard tell of people using "Bluestone" to wipe out the leech population, it also takes the other fishes out as well.  But since you are preparing for the addition of fish, this might be a great opportunity to eliminate the leeches completely, as well as any mosquito larvae. 

Native fish would not work or there'd be no leeches in the lakes....
the electricity would work too, but it sounds like too much effort, and if you were to get the local cat/skunk/raccoon, or dog some activist would be screaming.....

http://en.wikipedia.org/wiki/Copper%28II%29_sulfate

Not sure on your pond size, but it wont take much to do the whole thing,....I'd probably keep the stone in a netted bag or something so that you can remove it from the water....

Just a few thoughts.

HTH
Ciaus

A very interesting thread, please update as you move forward.

[JetJumper]

the electricity would work too, but it sounds like too much effort, and if you were to get the local cat/skunk/raccoon, or dog some activist would be screaming.....

If its on your own property, its not your fault something goes into the pond while you have the juice turned on.  Put up a sign, if it doesn't read it, then TOO Bad!  You covered your butt.  (Yes I know animals can't read - But I get annoyed at neighbors cats who come over to my garden beds and make it their own litter box.  If a dog has to be tied up, then why not a cat too)

Sorry, just venting. 

I vote for lighting it up like a Christmas tree with Electricity and Zap them good!

[Brent Shaver]

If you pick a day that it is hot and dry, and hasnt rained for at least 3, there is no way you would ever feel the current generated as the soil is dry.  As for stray animals, you would only do this in daylight hours anyway so just be around as it should never be left unattended at any time.  Animals are the least of your worries, should a child get to close and fall in..  well enough said.

If you monitor the job at all times while running then you should have no casualities other then the leeches.

This really isnt a dangerous way to do it.  Keep in mind if you touch an electric fence for cattle all you get is a very sudden and quick wake up call, not life threatening.

[cdylnicki]

May I inquire as to the outcome of this matter?

eg: Did you shock those blood sucking leaches or what?!