Pond Boss Forums AERATION Should I aerate? Was it the aeration?

Last year I had a 100% fish kill of my trout. I have a 2- acre pond in the Catskill Mountain region of NY. The pond is bottom spring fed and in the open, no shade. The max depth is 23 feet with most parts about 15 feet. In a drought year I will drop about 12" max

In March 1999 I stocked 200 9,10 and 11 inch trout. In the spring of 2002 the fish were 17-19 inches. Since the stocking in 1999 I did not have any fish die from unatural causes.

Last year we experienced the drought and an unusually hot year. I was iced out before February ended, we had 95 degree weather in May, by July 4th I had lost most of my trout. The fish died on the surface sucking air, they were all fat and healthy. I lost every one of them.

My question is; did I make a mistake when I aerated the pond with a bottom diffuser? I never had an aerator during 1999, 2000, and 2001. I installed the aerator in March of 2002. I realize 2002 was the hottest weather, because the ice was out 45 days earlier that usual the mean temperature was already higher. I ran the aerator all night, seven days a week. Would I have been better off not mixing the cooler water from the bottom?

I restocked 100 fish last October, they are doing fine. I don't know what to do for this year, change the aerator? Go to a Splasher? If I aerate do I do it at a different time of day?

Any help would be appreciated.

Thanks
Mike

See the discussion under Questions & Observations the topic of "Trout" by jdmcalf April 19 2002. These comments & advice should answer your questions. If you still have a question try a repost here. The bottom diffuser probably made the bottom water too warm esp since you ran it all night (too long). Did you monitor the bottom water temps as you ran the aerator during the summer?

Unfortunately I did not know better; I did not measure the lower layer temps.

Thanks for the reference to the past post.

Mike

Guys,
I've got a similar question about aeration. I've got a fountain I'm using in the summer, but I was planning on purchasing a bottom diffuser for the winter. I live in southern Michigan and my pond is close to .5 an acre and approx. 6 feet deep. Can/should I run this diffuser 24 hours a day or is this not a good idea? At 6 feet deep, I don't have a thermocline so that doesn't come into play. Whatever help I can get would be appreciated.

A 1/2 acre pond 6' deep does not need to be aerated 24 hr a day unless it is fertilized or has a heavy, dead organic load (lots of leaves, dead weeds or algae). Run times will depend on type of compressor and diffuser size. MSU & DNR contend that ponds in MI are more subject to winter kill if less than 15 ft deep. Your pond is a very good candidate for winter kill and a weed factory. Think about rebuilding and deepening the pond if you are serious about raising fish long term.

Mike-As Bill mentioned i learned the same way you did from the school of hard knocks. The bottom diffuser is fine to run in the winter at night to keep the ice off, but to run in the summer is a disaster. You and i had the same exact problem. The bottom diffuser mixes the water colume and will not provide a cool refuge for the trout. I lost 160 Scam Trout the same way. I solved the problem by installing a Kasco Top water aerator and run it at night and on cloudy days. When i installed it the fish immediately left the surface and i didn't lose a fish again due to oxygen. I also run well water during the hot days to keep the water on the deep end cooler. Sorry you had to learn the hard way but thank god for this forum. You can find Kasco on the Internet. Expect to spend some cash to get a good one.

Bill, thanks for the post. You're right about a weed factory. I do a pretty good job keeping the weeds in check with chemical treatments and raking. At this time, the money is not there to deepen the pond. I was hoping that running an aerator during the winter would prevent a winter kill. Do you feel that it won't?

JD. thanks for the reply. Yes it was a sad lesson the hard way. I had been so successful with this stocking.

I am interested in what model aerator you used and what size pond you have.

Mike

Mike-my pond is just under an acre. The brand of the Top Water Splasher is Kasco. From what i read here and from my sources once you buy one and run it 1/2 time it will last 15-20 years. I went and put a 230 Volt 2 horse in as it is cheaper to run 230. I don't think you can buy one(2 horse) at 110. Look under my post in Q and A on trout and the systems are explained well. If you buy a 2 horse that will be plenty for up to a 5 acre lake. If you do a search on the Internet you will find the suppliers. Let me know what you decide and how it is going. One other thing that i learned this year is i was losing a minimal amount of Trout this spring. I called my consultant and he asked if they were females and they were. They looked drawn up and stressed. What he said was once they hit 1 or 2 years the females will re absorb the eggs as they cannot spawn in a pond. During the second year some of them die when trying to spawn and this is natual. I lost three out of probbly 80 females. I am intrested if anyone knows the scientific reason for this occurance. Have a good summer.

Jeff

Jeff,

Two points:

I don't totally agree with your finding fault with the diffuser system. In my small pond I run it 24/7 but shut it off when air temps rise to 80 degrees. However, I also run enough 51.6 F. aerated well water in to keep temps down in this small pond from some time in May to September 24/7. If you have a smaller pond like me (1/12 acre 88 by 59 feet)with a few hundred pounds of trout the diffuser is important to help break down wastes etc. I am considering getting an aerator similar to yours to run at night in the summer as I keep upping the pounds of trout I raise. If your pond was small enough to keep cool with the aerated well water than you would be fine.

As far as the female being stressed by reabsorbing the eggs that does happen. They are not finding the right substrate and flow to cause them to build a redd and free the eggs. Therefore they reabsorb the which is stressful. That's all their is to that. I only buy male fish for my pond mainly because that is what my customers as most want them in their full spawning colors and kypes.

wingfan - The bottom aerator will in MOST cases help reduce the chances of winter kill. Winter kill will depend on severity of winter, location of diffuser, species of fish, and organic load on pond bottom. Diffuser operation all winter will cool the pond water to varying degrees below 39 degF which is quite stessful on the fish. A latent death in early spring may occur.

Cecil-I probbly spoke out of school about the difusser. I use mine all winter,(at night to keep ice off) but turn it off when the spring and summer hit. I am not heavily stocked with trout and do not feed them except for watching them with family eat the pellets. I did have a leaf problem but put up some snow fence and they really caught the better part of them. I agree with you anology of the diffuser and should have been more specific. Thanks for the feed back on the female spawn also. I put 1/3 of the pond in gravel and run some water over the area for a few weeks. My consultant said that may help cut down on some death loss. What is your opinion?

Thanks- Jeff-

PS. curious to what your trout are gaining on your program from stock to harvest with feeding.

JD,

I believe your approach is good with your method of aeration for your lower density.

As far as growth from stock to harvest I was dumbfounded by the gain in weight last year. My brooks went from 10 inches to an average of 17 inches in 11 months and close to 3 lbs with one just under 4 pounds and 19 1/4 inches(see final weight of brook trout on web site under "brook trout"). The brooks were yearling when I got them and that means all the brooks I harvested including the biggest one were just under 2 years old at harvest.

My browns and rainbows were planted with a variation of a half a pound up to about 2 1/2 pounds, and upon harvest most of the browns went from around 4 lbs to close to 8 lbs (see website listing of brown trout for final weights). I had lots of browns in the 6 lbs plus range.

I had four rainbows that were over 8 lbs with lots from the 4 to over 6's. I did have two or three rainbows that didn't seem to grow at all or there were some very small ones mixed in when I planted that I didn't see. (See final lengths and weights on websites under "Rainbows."

Feeding them twice a day can really make them grow but there are downsides. My water is really fertile and this year the aquatic weeds are going bonkers. I will draw the pond down this winter to see if I can kill the weeds. I believe one of the reasons my trout grow so fast is the water gets a little warm in summer but not too warm. It's right up there in their peak metabolism temp range for them. I do overfeed too which is not good, but since my trout vary so much in size it is hard to determine how much to feed. As far as feeding to satiation that does not seem to apply with my trout. They never slow down and I know I am feeding them enough as they are all quite stocky.

Cecil- i have looked at all of your fish and also take people to your site who do not believe me on the performance. That has to be so much fun to have those tremendous closeouts. Do you have a shrink wrap machine, and when you sell them are they just froze and sold with internal organs in? Also do you ever run out of stock? If you do i could take some pictures and show what i have. In fact you are the one that told me what i did have. haha. Let me know and i will fill your back orders if they exist. That would be a blast.

Take Care-Jeff

JD,

I do have a foodsaver and shrink wrap them with it although the ones that make replica fish do not want me to. Apparently the rough side of the material makes an impression although I can circumvent that somewhat first by freezing them on plastic and then shrinkwrapping them.

As far as filling backorders that is a possibility. What species and sizes did you say to you had? Are they flawless as in fins perfect etc?

I steer away from being a middleman but may refer someone to you if you have what they are looking for.



Cecil

Cecil-Rainbow and Scam. All sizes from 1 lb up to hopefully 8. Haven't seen any inperfections on any fish. My supplier has some of these fish that he takes up to Colorado that are 12-15 lbs. For the big ones he get $225/fish. Unbelievable! One of the resorts charge $3500.00 for three days catch and release only and you can fish from 6am-10am and from 5pm until dark. He wanted me to raise some for him but i didn't want all the problems associated with feeding that much feed in a small pond.

jd