Pond Boss Forums INTRO Questions & Observations Where have all my fishies gone?

A little background, new dug out pond about .7 acres. Filled last april, stocked with 350 blue gill, & 70 cat fish in may last year along with minnows. added 70 large mouth bass in august last year and at this point everything seemed normal. In nov. or dec. noticed 25-30 blue gill & 15-20 catfish dead at edge of pond. The 1st of january I added an areater sp. My son started fishing this spring with no luck, In may I noticed about 3- dozen minnows dead at edge, My fish hatchery guy was not concerned as he said it was probably old age. Early june I found Probably 2-3 5 gallon buckets full of dead minnows! Now he said he is concerned. And asked me to fish the pond good to see whats in there, well besides a catfish every 3-4 hours I would say nothing. Property is 6 acres that all run to pond, Would weed & feed on my grass cause this? We have a pool about 300 ft away that we had to drain twice last summer?? pond was filled with well water, pond has good natural bloom, very low visibility. Sorry for the long post, just trying to give a good background, I guess I have to restock, just dont want this to happen again, any help is greatly appreciated.
PS. If the rest of those fish died,why didnt I see them at the edge?????

What is "very low visibility"? .. 12"? 6"?
How often do you visit the pond?
Have you seen evidence of preditors which could have eaten some floating dead fish without your knowledge?
What size LMB, BG, Catfish (Channels ?) did you stock? Were the Catfish large enough to have eaten the LMB fingerlings?
My first guess with limited info would be that you have too much bloom causing depleted DO in early mornings. If vis. is very much below 12" the algea will consume more oxygen than it produces in early morning hours which will in turn cause it to partially die & the decaying organic matter adding to the low DO in the pond. Could this be the case? .. maybe .. duno. Give a little more info & maybe someone with more knowledge will reply.
Ric

Ric, At full bloom your hand is barely visible at 2 inches, otherwise 4-6 inches.The pond is visible from the house and im down there 3-4 times a week average, maybe less in the winter.
I have seen maybe 2 pelicans and blue herrins down there in the last year, they leave when you open the front door.
Channel cats were 3-4 inches, blue gill were 1-2 inches, we fished in late august just before adding the LMB which were 3-4 inches and caught cats 8-10 inches and blue gill 5-6 inches long.
In november or december I noticed lots of fish trying to breath at the surface, thats when I ordered the aereator. PLEASE HELP thanks mike

2 inches!

It sounds to me like overfertilization. Yes, lawn fertilizer can definitely cause this. If this is the culprit, the answer is simple. Restock and don't fertilize your grass so much, particularly early in the spring before the rains.

It's also possible, but not necessarilly likely, that the chlorine in your pool caused a kill. Given the difference in volume between your pool and your pond, I don't know how likely it is. If the pool was superchlorinated, it might have happened.

There are many reasons why you might not see all of the dead fish. Predators (coons, herons) are a likely culprit. Some fish may sink and you'd never see those.

The aerator may also cause fish kills if it's not the correct type or size, or if it's not run correctly. I generally recommend a bottom-draw fountain or bottom diffuser air pump. These should be run 24/7 from March through October in southern climates. Many run them year-round and that's not a bad idea either. There are other variables such as water depth that also have to be considered when sizing an aeration system.

Weed and feed is very bad when it comes to fish , water, yard , whatever. Go to an organic usage of Corn Gluton for the weeds in spring and fall, and Green Sand or another organic for fertilizer. In addition to doing harm to the water it also harms pets, kids, etc.. More and more horticulturists are going organic and we fish people will be right behind. And I am a roofing contractor so I have no financial insentive for saying anything about the products. Good luck.

Mike
Cat's were 8-10" when you added 3-4" LMB. I'm sure they took quite a few of your LMB fingerlings. Visibility should never get below 12". I don't think the pool water was the culprit ie: the chlorine would have killed the algea bloom along with the fish. Although you don't want chlorine in your pond unless you drained directly into the pond it should have been diluted sufficiently by the time it entered the pond not to cause damage .. depends on the size of your pool & how well you keep it treated. I'm not sure how to decrease the bloom therefore increase vis. other than flushing if you have some way to increase water flow but that is what ultimately must be done to save remaining fish. Describe for us your areation system along with how often you operate it.
Ric

ps: Just read fishmans post. He gives excelent advise. I've read many of his post, even rated him .. highest rating.

Thanks for the responses, yes the visibility was down too 2 inches last summer but we had not done any ferterlizing last year? this year the visibility is a little better and the first fertelizing was done 6-8 weeks ago, 5 10,000 sq. ft. bags over 4.5 acres & none near pond edge. Does nobody with a pond use weed and feed on thier lawn?? I would like to restock, just dont know if I should yet, should I treat the pond with algeacide first? Should my water be tested for something? thanks Mike

Ric just saw your post, The areation system is a single pump with a single round diffuser set at about 5-6 ft deep, deepest part of the pond is 8-9ft. Fisherman since the fish kill came after most of the weed and feed went down, does that shed any light? Dont know where to turn, Thanks Mike

Mike
I'm sure Fishman will respond but I'm guessing the 'feed' part of the 'weed & feed' hurt more than the herbicides. I am trying to make clear that I think your MAIN problem is too much fertilizer = too much bloom = Low disolved oxygen = fish kill. Never let vis. get below 12"!!! I would not restock until the water clarity improves. Wish you the best.
Ric