Pond Boss Forums GENERAL QUESTIONS Muddy water Help please. I need to do a fish kill

I live in Florida and have a small hobby farm. One day my khaki Campbell duck was in my pond which is about an acre, give or take, it's freshwater, spring fed, and while my suck was swimming something from under the water tried to pull her under. My husband fired at it, it let go of her and I got in a boat and got out to her and got her out. She ended up dying, however I did not see any puncture marks on her leg or foot. I bought some minnow/crayfish traps and baited them and set them. I have pulled out a greater siren (about 2.5 foot long) and amphiumas (two toed) and American eels. I have come to conclusion that I need to hit the reset button on my pond to make it safe for my pets and even my kids. The pond is in the front yard. I have read about rotenone, but it seems like that will be expensive to do. Due to a previous car accident and my health my husband is the only one that can work and we refuse to be a drain on the system. I have also read about hydrated lime as a way to do a fish kill. I am in desperate need of help and FWC has shifted my calls from place to place and cannot give me advice. What would be the best, most effective, reasonably priced way to kill everything in my pond to make it safe for my pets? Any advice would be appreciated greatly. Thanks!

Welcome to the forum.

I would go to a rental place and rent a 4" semi-trash pump along with suction and discharge hose. Drain the pond down so the water volume in the pond is cut by 75%.

Go purchase a pH testing kit (I am not sure if the cheap test strip kits will measure as high as you have to go to kill fish). Spread enough hydrated lime in the pond and into any places that have any standing water and check with the test kit to ensure that you have reached a pH of at least 10.5, a minimum of 11.0 is what I'd shoot for.

How much hydrated lime to use? I cannot answer that question. You can answer that question yourself by getting that test kit, and a bag of hydrated lime from the local big box store. Fill a 2.5 gallon bucket with water from the pond, measure how much hydrated lime you have to add to the bucket (by weight) to reach 11.0 pH when tested. Then you can do the math.

For a rough guess, take the surface area of your pond, multiply it by half of the maximum depth and that will give you a rough idea how many gallons of water is in it. Then it's a simple measure to do the math to determine how much of that specific hydrated lime you will need.

Wear protective clothing and protective eye wear when messing around with the hydrated lime. If any gets on your skin, flush it immediately with water or you will get chemical burns from it.

Oh, you will have to keep the pets out of the treated water until the pH gets back below 9......... The less water in the pond the less hydrated lime you need BUT the less water in the pond means the more puddles there are which are a PITA to walk around and treat.

Rotenone is the easiest to use, just get the water volume down to minimize water volume but still not have any individual puddles to treat, and dose it at the rate of 1 gallon of 5% Rotenone to every 195,500 gallons of water. You need a aquatic chemical applicators license to purchase Rotenone.

Thank you soo very much. I am going to call around for the pump. I appreciate the information!!

Any idea of anything else that could be in the pond that could attack a duck? I did remove snapper turtles but the head was still attached as was her leg. I have seen snakes but no marks on her to match. Could there be something else I should be looking for?

Is some kind of gator/crocodile a possibility?


One thing to think about if you try to pump the pond down.... My impression is that some Florida ponds are in existence due to high water table levels. If that's the case with your pond, you may not be able to effectively pump it down.

The rental places should have the pump.

Sunil is correct, if you rent the pump and it fills back up overnight, then forget about pumping down and then treating. Spring fed pond could mean that you can't pump it down and have to treat the whole thing as it is.

With no teeth marks on it, I'd suspect a large catfish. Any feathers missing from the part of the duck that was in the water when it got grabbed?

Another question, is the duck a mature one or a duckling?

She was a young adult, fully feathered. No there was no feathers missing. All I could see was her one leg pulled under and her struggling. My husband fired into the water, missed the duck, but it let go immediately. A couple of hours later other ducks got into the pond and something kept hitting the top of water while getting closer to them. They got up on the bank but whatever it was would flip water at the surface near where they were last at. Finding the random things I have in the pond I was just wondering if I could be caught off guard pulling or trapping something else I didn't plan on. I have not read where the amphiumas, greater sirens, or eels have not been documented attacking a duck.

My husband did say it is a spring fed pond. Should I still try to pump it as low as possible first?

Melody, I don't know if you missed it, or had mentioned anything earlier, but is there a chance you have a gator(s) in the pond?

Regarding pumping the pond down, 'spring fed' might be a concern depending on the inflow. Obviously, if you can pump out faster than the spring(s) feed in, then it could work.

But I was wondering about the water table itself. If you dug a hole, say 4' deep, would it start filling by itself? In other words, by going down 4', you may hit the actual water table.

Please be sure the pump/hy lime will work. Usually a good idea but not sure it will work in your area. Much of Fla is spring feed through limestone and I have doubts that pumping and Hy lime will work. Might try a treble hook (large) and hunk of meat on a cable and see what happens.

I have watched a LMB pull an adult Mallard hen halfway under water and hold her there for 10-15 seconds. After eating all of her ducklings. And I'm not trying to grow big bass.

Certainly the type of critter that pulls down a big duck could be a species other than a fish and in that case all the pumping and chemicals won't help (reptile attack?)

I agree better sampling before nuking the pond is wise. Baited jug line should catch a catfish over time. Large LMB would be on the list of fish that would ambush a duck in such a foolhearted fashion.

If the critter is still in the pond it/he/she may take another pass at a big lure that acts the same way on the surface. You said this same critter kept taking passes as the other ducks. A very large wooden lure mimicking a mouse or frog on the surface is pretty hard for a big LMB to leave alone. In northern lakes a pike or musky would be happy to swipe at a duck but I don't think that is on the list of likely species in your pond.

The other thing that is odd about your description is that she seemed to have been pulled down by 'one leg' I would think a large bass would try to use vacuum to suck in the body of the duck and I don't think a LMB can grip one leg with its mouth and hold it down.

Toothy predators (pike, pickerel, gar pike, musky) are more likely to use their jaws to clamp on a leg and pull it down. I would say this technique is also favored by alligators.

If you did decide to start pumping down the pond and were successful you may be able to spot the large fish as the water levels go down and all the remaining creatures are concentrated in a smaller area.

A one time treatment with alum or water clearing pellets might really help. If the visibility was suddenly 3 feet down or more you more easily could spot a large fish.

Lots of good advice you are getting on trying to correctly identify the culprit before deciding on the solution.

A good game camera (or video security system if appropriate) might be another good tool for you.

A game camera might not catch a snapping turtle crawling up the bank, since he would not have a heat signature. Therefore, you might have to try some time-lapse shots or video.

However, a visual medium might show you a turtle, small gator, otter, etc. at your pond.

Further, the up-front investment would not be a total waste, since it is always nice to have a little surveillance on your property.

Hi! What part of florida?

My pond doesnt have eels that ive noticed, but ive got gators when its warm