Pond Boss Forums GENERAL QUESTIONS Help Dead Fish

I took a look around the pond today and seen one large fish in the middle of the pond. Until I get it out of the pond, I won't if was result of damage from a heron or a raccoon. Plenty of tracks around the pond.

The disturbing thing I noticed was that along the edges I had small fish (BG)? dead or going to die. Approx 30-50.

Here are some pictures:





I treat a few willows trying to grow on the pond bank with round up and I very careful not to get any in the water and that was a week ago.

Any thoughts?

Glysophate (Round-up) is mildly toxic to most aquatic life, but the real problem comes with the use of surfactants in combination with Glysophate. Many of these are EXTREMELY toxic to fish and other aquatic organisms. I would temporarily cease any herbicide use and see if the problem corrects itself over time.

Major temp change lately??

Bossone,

Sorry to hear about your problem. The fish in the pics look great! Are they getting enough oxygen??? Do you now what your D.O. content is in your pond? Do you have a air system setup? Have you done any kind of basic water test?? Just to make sure your PH and all is on Q? Just throwing out ideas. I wouldn't think a little bit of round up would kill a bunch of fish?? But I am no expert on that??? Sorry bud and good luck.

Not much of a temp change than what you have add in STL. Bit cooler the last few days.

RC: none of the above. If it was an oxygen problem wouldn't I have issues with my bigger fish?

My big fish are doing ok, its just these small ones. I could see some still gasping. These are BG correct?

Well you said you saw one large fish out in the middle?? Do you know what was wrong with it yet? Was it out there piping for air? You may see more if it's a D.O. problem. Are these smaller fish near by where you treated the willow? If so it could be from the round up. Maybe some got in the water? Like I said no expert here just throwing out ideas of what it could be? Have you had a lot of rain as of late? Maybe something washed in from the water shed or washed off your willow tree and into the pond??


P.S. Yes those look like BG to me!

No the big one is dead and I suspect it is unrelated to the ones on the edge. I'll be keeping a close look to see if there are more bigger fish dying. I'm betting the heron or the coons got a hold of him.

The little ones are not where i sprayed over a week ago. No rain, in fact we are down to our lowest level, but still have a fairly good depth left.

Hmmm. Well theres not a whole lot to go from then. Unless it's just a freak thing I would be very watchful of my fish though. How big is your BOW? If it's not to big and you have less water in it then ever before??? You could have a start of a D.O. issue? Like you said I would be mindful of any bigger fish coming up to the surface. And if you can get a basic water test kit from a local place there and test your water. A simple dip strip would be better then nothing at least it would tell you where you stand on PH and Nitrates and Nitrites and such. I would take a few readings in different spots your PH should be around the 6.4 to 7.3 range if it comes up really low like 5 or under or really high like 8.5 that could be a reason for the younger dead fish. Or you could have had a big swing in PH at some point and that is why the fish are dying? A lot of maybes for sure! Let us know if you find anything out.

I stand corrected.....the bigger one is still alive, but dying.



1/2 acre pond, 17ft deep, down about 5.5 ft. How do I get the DO up?

I ran a sample into my bottled water company and they tested the PH and said it was a above 8.5.

What would of caused that and how do I treat it?

Hey Bossone,

Maybe we can get some more experts in on this post. I am not sure how to lower your PH I know how to raise it with AG lime but lower it. I am not sure what to do for that. Maybe someone else can chime in and answer that one. Above 8.5?? Wow I would say that's getting to high for BG and LMB. I may be wrong but that seems high to me. Lets see what anyone else says. Getting D.O. into your pond?? I know in an emergencey guys will use trolling motors off their doc and run them to get the water moving. Small outboard motor if you have one? It's all about getting that water moving and getting some of that deeper water to the surface to get some oxygen. PH can be all over the place that's why I said for your to get more than 1 reading. Testing for D.O. is a bit harder unless you have a fancey D.O. test kit. In your situation it could be both or it could be 1 or the other causing your problem. Your PH being over 8.5 concerns me. Do you have any plants in the water to produce D.O. during the day?? I know your chomping at the bit to do something but lets wait and see if we can get one of the big dogs in on this and see what they have to say first. I don't want to steer you the wrong way and make things worse.

Agree.... and that was one same spot. No plants in the water.

We will wait... I have a call into Nate to see what he says.

I hate losing any at all..... it was 1 of 26 LMB that I enjoyed feeding every night so I can eat them at some point!

Ok keep us posted and good luck sir!

Update: bass must of recovered as he's no longer floating. Instead I did find a 4 inch bluegill that was swimming circles to the edge.

Typically it's a feeding frenzy when I feed them of an evening, with the LMB leading the charge. Tonight there wasnt as many and only seen 2 bass.

Pond looks good this morning and no dead fish are floating. Nor are there any fish on the surface gasping for air, something Nate asked me to check on.

I'm dumbfounded.