Fish dying

[czechsonofagun]

Completely puzzled. In 4 years I never saw a dead fish in our pond - and the Sunday before the last one I found:

2x big cat fish
2x small bass
1x small catfish
3x big blue gills

The smaller cats and blue gills still come for food, and there was no death since, but I have no idea why it happened. And I voted not to diasect corpses, it was hard enough to get them out of the pond.

As far as I know there were no chemical spills, we didnt have rain to wash the road in the pond recently and as I said - in 4 years I didnt see a dead fish and all the frogs are happy as ever.

Also the food is the same catfish food i use since spring.

Ideas anybody?

Thank you

 

[fishman]

Sounds like you might have had a mild case of low dissolved oxygen in your pond. If your pond is low, the water is hot, you're feeding your fish, and the water is green from an algal bloom, you are at greater risk. This pretty well describes a lot of ponds this time of year.

Check in the mornings to see if fish are at the surface. If so, they are likely trying to obtain oxygen in the thin saturated layer present at the surface of the pond.

If you've been feeding for 4 years and not harvesting fish, think about it . . . all of those fish are now bigger and need more O2.

Most people jump to the conclusion that chemicals are responsible for fish kills. However, that is rarely the case. The vast majority are oxygen related. A few days of cloudy weather during which the phytoplankton and aquatic vegetation uses oxygen rather than producing it, and you have a problem. Many fish kills come a day or so after a rain event, which makes people think something washed into the pond. Again, it's usually low oxygen.

 

[czechsonofagun]

Thats a good point, fishman.

I run a fountain for 2 hours three times a day, would think it is enough. Maybe it is time to add a compressor.

Also I feed only since last fall, there were some old fish left from previous owner, but thats when I put new small catfish in.

We harwest blue gills from time to time for soup, but from what I can say there are no that many fish in the pond - from what I see in the feeding time.

 

[knute_m]

With the recent hot spell and lack of rain, at least where I live just west of of the Blue Ridge, I too would think it is a lack of dissolved oxygen. So far, my pond is doing well, and the fish appear happy and healthy. But, my level is about a foot below the top of the standpipe.

But, if you really want to get some expert advice, Pond Boss magazine hosts a fantastic forum, much like TBN. There truly are many experts on the site who provide an invaluable service to pond owners. The forum is at:

http://www.pondboss.com/cgi-bin/ubbcgi/ultimatebb.cgi

Good luck,

Knute

 

[Soundguy]

I agree with the others. Any time i see a fish kill.. and the larger ones go first.. that is a sure sign of o2 problems. An algea bloom will do it.. fertalizer runoff or other decaying matter will increase BOD of the water and burn the 02 out of it.

Aerate or run a fountain toincrease water surface area. If water is extremly low.. you may considder adding water depending onthe size of the pond.. etc.

Soundguy

Completely puzzled. In 4 years I never saw a dead fish in our pond - and the Sunday before the last one I found:

2x big cat fish
2x small bass
1x small catfish
3x big blue gills

The smaller cats and blue gills still come for food, and there was no death since, but I have no idea why it happened. And I voted not to diasect corpses, it was hard enough to get them out of the pond.

As far as I know there were no chemical spills, we didnt have rain to wash the road in the pond recently and as I said - in 4 years I didnt see a dead fish and all the frogs are happy as ever.

Also the food is the same catfish food i use since spring.

Ideas anybody?

Thank you

 

[crk133]

could someone have dropped an m-80 or equivalent in there?

 

[Soundguy]

Concussive blasts would probably only have effected a small group of fish right around the device.. I guess depending on the size of the explosive and the size of the pond.. that could have happened.. same with a monkey rig...

However.. a couple gallons of molassis might have done the same as well... Any bio matter ( including the dead fish themselves ).. will increase the BOD on the water body.. thus depleting it's O2.

Soundguy