I have about a 1/2 acre pond that was really nice and clear in the spring then heavy rains hit and it has been REAL muddy ever since and will not settle out. So I added about 600lb of gypsum last saturday, has not done anything at all. Still chocolate milk. Should I add more? I spread it as evenly as possible then ran back and forth over the pond with my trolling motor.

Welcome starman to Pond Boss. Just a few questions to help us help you. What kind of fish does the pond have stocked and how many? Have you tried a jar full of the muddy water or a 5 gallon bucket to see if the water will clear when it is undisturbed? What part of the country is the pond located?

I am in northeast oklahoma, the pond has no catfish, just bass, bluegill and fatheads. Yes the water will not clear in a bucket, after reading some posts I may be way under on my gypsum, the pond is around a 1/2 acre maybe .62. but is a deep pond with few shallow areas. Maybe I need to add several hundred more pounds of gypsum. I added 2 gallons of liquid alum after the first rain in late spring but I just used a sprayer and only got a scum build up on top, I probably didnt mix it well and it wasnt enough. I would rather stick with gypsum though. How about hydrated lime? anyone used that? I know there are several posts about ag lime.

US Gypsum recommends 2000lbs per ac. I put in 2800lbs in my pond(1 &1/3ac). My pond went from chocolate milk with about 2in visibility to a beautiful clear green with 15in visability in about one month. Check your alkalinity and add ag lime as needed(check previous posts on this subject). Continue to visit this site as it will help you and I can recommend that you subscribe to the magazine.

Thanks...that is kinda what I thought, I need more gypsum, is it really better to mix the gypsum into a solution before applying or will spreading and going back and forth with a trolling motor ok too?

Get a 5 gallon bucket and figure out how much it takes and if it will clear the bucket. Then you can figure the gallons in your pond and how much to add.

Update...Took a 32 ounce jar and added about 2 teaspoons of gypsum (found some left in the bottom of a bucket) applied and presto, this morning the water was crystal clear. So, its just a matter of I need to put more in the pond, just have to get the calculator out! I think I may go to the effort of mixing in a drum and adding the solution this time instead of directly to the pond, any ideas on that??

starman66,

Are you up for an experiment? Cottonseed meal has often been reported to be a successful agent for clearing ponds(for example reference the latest issue of Southern Ponds). The recommended rate is 300 pounds per acre...a lot less than the gypsum....and it is widely available, at least around here.

I'm wondering if you would be willing to try your bucket test again but this time with some cottonseedmeal? It would be an interesting experiment to get a direct comparison. My thanks if you accept the request...no problem if not. Thanks.

Yes I will try that, I was going by the feed store anyway, I will let you know. It has 6 days since I added 600lbs of gypsum, I looked this morning and the pond is starting to look a tad better but that could just be from settling anyway I guess. I am sure the gypsum helped just didnt add enough to see any difference. I will give the cottonseed meal a try though.

question on the cottonseed meal, should I mix it and let it absorb in a drum first or just apply direct???

After thinking about it I will try the test with cottonseed but may wait on application because of O2 levels, we are like 105 degrees here. So I may go ahead with the gypsum and when the water cools later in the year try some cottonseed meal.

Yes, I was only interested in the test...like you said its probably too hot for actual application. Thanks.

I simply poured the gypsum out of the bag and let go into the prop wash from my trolling motor.

update...added 320 more pounds of gypsum on 7-22. Yesterday I could see maybe just a little clearing, not much. I will give it a few days to see what happens. The evening after application I noticed green streaks up and down my pond? The next morning it looked like chocolate milk. Like I have said, I know it works because of the jar test, I just need to keep going I guess.