Yes, a little bit, though not as carefully thought out (or carried out) as my original effort. Since the water level is restored and there is no exposed shoreline now, I wanted to see if there was any chance if I could get the visibility back that it would hold better. When I put the original gypsum in, I had a dump truck drop the load near the edge of the pond. There was quite a bit remaining in this pile, so I took a tractor with a front loader and scooped about a 1/4 bucket per scoop and dropped it at different points all around the edges of the pond (Yes, I was lazy.). The net result is that to the eye, it appears that I do have a little bit more clarity. However, the results were not nearly as dramatic as with the full 2500 lbs of gypsum and the spread application. The only other thing I am doing is watching the clarity in my new pond which has yet to fill. The new pond is just across a hillside, and the water looks just like the pond I have been trying to clear. Once the new pond gets full, I am anxious to see if the water will clear (either naturally or with my help) and if so, if it will stay clear in the absence of catfish. To me, if the new pond can clear and hold clarity, this will lend support to the idea that the action of the catfish may be the culprit in the current pond. Other factors such as soil type, pond construction, ph of water, etc., are nearly identical. From my experience, which is very limited, from your post above, it seems like the amount you are considering might be a bit low. I know from my jar tests and from reading here on the forum that a little bit of gypsum does not do a little bit of good. It takes a certain amount to reach a critical threshold and then boom...it does its work. However, from earlier posts I have read the advice to put in a little, then a little more, etc., until you reach the amount that is needed to force the suspended clay to clump and drop out of suspension. What you might consider is doing basically the same thing that you are considering in a test jar. While others have used a slurry method and applied to test jars, I was able to get good test jar results just by dropping in very small quantities of gypsum directly to a gallon jar. If the purpose of your test is to see if gypsum might have an effect on your turbidity, I think it would be easier to add enough gypsum to give you a positive test (clear water result) in the test container. I'm thinking that if you put in 150 lbs, then 300 lbs, etc, you might not get a positive result in your pond and so conclude that gypsum was ineffective. However, if you drop in 1/8 tablespoon, then 1/4 tablespoon, etc., you might get a good result and know that gypsum is the ticket, and then just have to determine how much to add to the pond. I hope to hear back from you and others as I am still battling this problem here.
