Pond Boss Forums GENERAL QUESTIONS Muddy water I want to try alum, too

My 3 year old 1 acre 8 foot deep aerated pond has had a suspended clay problem from the beginning that I have been able to keep somewhat in check by keeping a good bloom going. After the initial beautiful spring bloom this year, the water clouded up and I got too busy to fertilize regularly. Now, no amount of fertilizer seems to get the bloom going again. No catfish in the pond to stir things up, just hybrid bream and a few bass. My chemistry is great, since the pond is fed only by well water. Alkalinity-250 ppm, Hardness-180 ppm, and a pH of 8.4. The pH usually runs around 8.0 but with all the rain lately, it has a tendency to go up slightly. I was thinking about alum to clear the water up a little so my bloom can get going again, but I have a few question for the experts. Searching this forum, I find that most have had good success as long as you follow directions. My pH and alkalinity is high so I don't think I would have a buffering problem or pH crash. Has anyone used baraclear or phosclear before? I think the phosclear has a buffer in it already. Are liquid forms better than crystal? From what I read, the alum causes the clay to bunch up and sink to the bottom. How thick a layer does it form on the bottom? Does the layer of particles eventually mix with the clay on the pond bottom? My pond has been aerated since day one so I have absolutely no scum on the bottom and I would like to keep it that way if possible. Since alum is caustic, does it become inert when it combines with the suspended particles and sinks? We swim in the pond, too, just like the fish, and I wouldn't want to do anything that would keep us out or endanger anyone's health. If the alum works, how often should I treat? Is there a "X times per year" threshold or maximum? Last question, will I be required to turn in my pondmeister's badge because I haven't been able to solve this problem on my own? Sorry for the long post and thanks in advance for the advice. I've learned alot from this forum, I just hope I can get enough experience to return the favor someday.

http://agfacts.tamu.edu/D11/Calhoun/Mar/Recfish/Pondmgt/mudpond.htm

Here's a link. I'm looking for the best threads to reference for this. It's all about finding appropriate effective concentration levels, then applying cautiously so that you don't create a pH crash.

Not an expert on this but don't understand how you can have a beautiful bloom and a suspended clay problem. Just how bad is the clay? Do neighboring ponds have the same problem? Why do you have a clay problem?

BTW, most of us proudly displayed our Pondmeister badges. After we learned just how little we really knew, we tossed them.

Most of the shallow ponds (<12 ft. deep) around here have a similar problem. Deeper ponds seem to do better around here for some reason. The deeper ponds communicate more readily with the water table I'm told and that aeration doesn't "stir" a deeper pond as much. I had the problem from the get-go so I called my area LSU AgCenter aquaculture specialist. He came out and looked at the pond, took samples, and diagnosed the suspended clay problem. His suggestion was to try getting a bloom first, because as the bloom dies off, they catch some of the clay particles as they sink and bring them to the bottom with the dead plankton. He did say that if it worked, I would have to watch the pond closely and try not to let it get ahead of me or I might not be able to get a bloom going if the water got too milky. Since the pond was only 3 months old, the water was still clear enough to get a bloom going. Sure enough, when the bloom started to die off, the water cleared nicely. About 24 inches on the Sechi disk. Then it would start to get a little milky. The pond is kidney-shaped and I have Vertex double 9-inch aerators in each lobe of the pond running 24/7 so that keeps my water moving, too, contributing somewhat to the suspension problem I suppose. I hit it again with 11-37-0 and the cycle repeated. I have been doing this for 3 seasons now with some success, however, this summer I got preoccupied with switching from grain crops to hay and trying to start a new house and the pond got away from me. I guess I'm just looking for a fix that will get me back into my regular routine. I spoke to the Agcenter guy and he suggested gypsum or alum. I wanted to run this by you folks, too, to get all the input/opinions/education I could before committing. Thanks for the replies.

I have never considered alum. However, I did research gypsum. Take a look on this area at the Calculating Gypsum Amount thread and my April 19 post regarding an answer to my questions from US Gypsum.

DKFarms: I am in SW Louisiana (Lafayette). Who was your LSU specialist ? Do you have contact info for him ?

This is a must read fact sheet on the subject. If you read this fact sheet and then need more info then ask again and we can go over the fertilizer method you tried.

I assume you do not have muddy water run-off. If your well water does not have a clay problem and you got it under control by the fertilizer method then my guess is the aeration is causing the problem by re-suspending the clay solids after they drop out of suspension. You may need to elevate the diffuser off the bottom some. If you try either alum or gyp. and it works and then the turbidity reappears it is the aerator.

SRAC 460 Control of Clay Turbidity in Ponds

http://srac.tamu.edu/tmppdfs/13452410-46...d1522b32031395e

From SRAC Water Quality Fact Sheets

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