Pond Boss Forums INTRO Questions & Observations Bluegill pond should I be concerned?

Coincidentally or not, with cooling temps my small 90 by 40 foot bluegill pond (for growout of bluegills only) has had visibility reduce considerably although it is hard to tell water color, and how much of it is phytoplankton due to the aquashade I added this spring. It seems to have an odor to it (the bottom smells like hog manure as it gets exposed from draining). I've drained it down about 3 feet and I'm now running fresh well water into it. (Well water is close to same temp of water in pond). Once it gets up to the top I will drain down again and top off with well water again. I'm hoping to eventually freshen the water this way.

I was able to catch a couple of bluegill on a flyrod and they appear healthy, and they are feeding but the water looks terrible. I'm not seeing any mortalities.

I use a diffuser and have been mixing the water column all summer so I don't think turnover should be an issue unless the diffuser isn't mixing the water column well.

Any thoughts? Pond is only about 7 1/2 feet deep on the lower end. I'm thinking the fish biomass may be higher than I realized and I've lucked out due to lower water temps preventing an oxygen deficiency.

Cecil:

How many did you put in, and how big were the BG you were able to sample?

Cecil,
Follow your instincts. If the water looks bad, it probably has problems. This time of year, even with aeration, I see a few heavily loaded ponds thick with blue-green or planktonic algae. Another thing to remember, if you can smell it, something is escaping into the air. That's a good sign. Remember, ponds fed often have a buildup of waste matter in the soils. When exposed to air, fish waste smells pretty stiff. And, when mixed into the water column in temperatures in the low 70's or even the 60's, a 'new' bloom can start up...as the dye dissipates. Follow your common sense. If the fish are valuable, flushing does no harm, and may help immensely.

Cecil - Bob's comments gets me thinking and this relates back to some of my comments in the Georgia Giant Post. As I recall you are using "blue dye" in this pond. It is possible that the blue dye retards the decompostion bacterial rate of the fish manure, thus the unusual odors. Freshly drained ponds typically have an odor, but I would not describe it as smelling like hog manure. Hog manure odor sounds atypical.

Heavy doses of blue dye may inhibit healthy and normal activity of the sediments. It certainly retards the benthic algae growth and resulting oxygenation of the mud water interface. Without adequate forage the burrowing benthic invertebrates may not be present in adequate numbers. I am not aware of any eco-benthic studies where the affects of blue dye have been studied.

Good catch, Cody. That's where I would go with it.

CB1 :

Our ponds smell like that evey time we draw them down. I think it has to do with methane gas that occurs when plant material decomposes in the mud and then escapes with the smell of muck decomposition when the water is off of it. As you know pig mess has lots of methane in it. Did it smell before the draw down? ewest

Thanks all Theo, Bob, Bill, Ewest!

Water's looking better already.

Theo, I put in 170 lbs. of blueglls (500 @ 6 1/2 to 7 inches). Some of ones I have sampled have grown about 3/4 of an inch. I guess that comes out to 1700 pounds per acre initial planting for this 1/10th acre pond! Holy crap no wonder the water looked like a sewage plant! I also had some reproduction but not sure how much. I've fed about 1 lb. of feed per day max as there seems to be plenty of natural feed in the pond both aquatic and terrestrial. The grasshoppers that blow in don't have a chance.

I plan on removing all the males I can this spring and putting them into an all male pond. This time of year the sexes don't look much different or the dye has suppressed their colors. I will try and reduce density substantially by putting all the remaining females into the bass pond and allowing the remaining fingerlings to grow. When I need more fingerling production I'll get some broodfish from the other ponds.

Ewest, the smell is I think primarily from the exposed bottom. Our soil naturally smells that way when it gets wet but not nearly as strong. My dad who lives on my property swears up and down there had to be a hog farm here at one time. A neighbor who lives across the highway and has lived here all his life says no.

I'd like to steer away from the dye in the future.Anyone know if I can create a stable algae bloom in a pond this small without it getting away from me? Maybe the feed itself would contribute to the algae bloom?

CB1 :

I should have remembered that the pond in question is really an aquaculture operation. Water quality at those densities is a entirely different matter. Below are a couple of fact sheets (first- ammonia , second-nitrite and third- general list of fact sheets on water quality )which may be of interest. The first 2 were news to me. ewest

http://srac.tamu.edu/tmppdfs/7182696-SRAC4603.pdf

http://srac.tamu.edu/tmppdfs/7182696-462fs.pdf

http://srac.tamu.edu/index.cfm?catid=25

ps : several of the events you have talked about in this pond are described in the one on ammonia.

Cecil - The reference that ewest gave for ammonia was informative. Two things, that I think apply to our situation, were noted from it. 1. The aquashade in your pond is probably inhibiting algae growth. High fish biomass is producing lots of ammonia that is not getting absorbed and processed properly by algae due to low density of algae (due to dye).

2. High ammonia levels are probably contributing to the odors. Also I recall you fish were acting unusual this summer in that they were in shallow water and not feeding well. Your quote - "Although I originally thought bluegills in my male only bluegill pond were concentrating on eating tadpoles, hence why they were off feed, I now think they are in a spawning mode."
The article said ammonia levels will increase in late afternoon. Your fish may have been showing signs of ammonia stress?.

Cecil, I think I may be onto something with this circular/horizontal aeration. Here's the photo.



Since I started this I have maintained Secchi readings of exactly .5 meters. I think this is something you could try. It's working beautifully so far.

I've been trying to fire up a discussion on the following thread but all anybody wants to do is talk about Georgia Giants. :p

http://www.pondboss.com/ubb/ultimatebb.php?ubb=get_topic;f=11;t=000125

P.S. This is also saving me the money of running a compressor.

Bruce,

Yes I saw that. Very intriguing. I think I will end up using some kind of aeration and I'm seriously considering what you have proposed. Thanks!

Ewest and Bill,

Thanks for the info!

Ladies and Gentelmen,

I don't think the pond was a bad as I thought. Once I drained down to below a foot or so the "hogsmell" did not persist and the bottom was clean clay without the mold that I saw near the max wateline (due to feeding sinking feed to fingerlings around the edges). I have drained the pond down to 30 inches on the deep end (pond slopes for easy draining) and I'm now filling back up to max pool with a well. Fish are even feeding in the cold water. I hope to cull out males come spring into another pond right next to it that presently doesn't have any fish. I'd do it now but all the fish are very pale in color and it's hard to make a definite determination of sex this time of year. I believe the dye also subdued their colors unless is has something to do with the fact they were originally from an RAS (Recirculating Aquaculture System).

CB1 :

Glad to here all is well with the pond. Even though the pond was ok I still learned a lot from the discussion you started. Thanks. ewest

Good deal, Cecil. I emailed Bill with some pictures of my big male bluegill that I've been raising, and they too have extremely muted colors. It's just that time of year.