Is aluminum sulfate effective if applied to a new pond floor before filling it with water? If so would it be wise to mix lime with it and would ag lime work or would I have to use hydrated?

Welcome to PB !!!

How do you know you need either/one/both ?

I'm in southwest Louisiana our ponds are extremely prone to suspended clay sediment our soils are very low in ph. I also have a pond right next to this one that is extremely cloudy so much so that it is effecting fish bite. From what I understand a heavy rate of ag lime will help to keep the pond clear I'm just not sure if it will be instant at the time of filling or will I have to wait for ph to rise? I am 99.9% sure that If I just fill pond without adding lime gyp alum not necessarily all of them but at least one of these I will have another mud soup pond.

Thank you for the warm welcome!

Welcome to the family. Have your water tested to see what's needed,then post the results and the brains will interpret the findings, lots of smart folks here that will set ya in the right direction. Tell us what you would like to have in your pond and goals. The more active you are on the forum the more you learn( others also)

I would lime it heavily while it is still dry. I would put any amount up to 8 tons per acre. It is very hard to get too much lime if you have acid clay.

No expert. Just what I would do and have done.

It's still being dug so I don't have any water currently. Would it work the same way to get my soil tested ? I'm pretty fimiliar with my soils around the area of the pond being that I'm a farmer and the pond is on my farm I have all my soils tested every year for my crops but I'm sure the top few inches of the soil profile differs from 6ft deep. As far as liming I have a spreader truck for the farm and my local aggregate service is 5 miles down the road. I may just load the spreader truck with lime and drive it into the pond.

Would it also benefit the fertility of the pond to put a few inches of top soil back over clay once im done digging the pond?

That is the way you are supposed to do it. Take a soil test and tell the lab it is a new pond bottom.

That is what we do. Run the spreader truck across the bottom in a large pond or spread all around the perimeter if the banks are too steep. Back up to edge and let r rip.

In my non-professional opinion based on nothing other than opinion unless you apply the lime measured in inches deep, adding too much will only make it last longer. If you have acidic clay it is probably about a 5 Ph with a buffer solution requirement out of this world. Get it tested though and they will give you a recomendation. Good luck getting a representative sample.

By the way, pay no attention to what I say. Better you have experts help you. But that does not stop me from having an opinion.

My main pond my NRCS agent recomended I line the bottom of the pond with stock piled top soil if I wanted non-turbid clay looking water (as thin of layer I could get spread). It worked as that pond has not had clay turbidity problems like other ponds that were simply left clay bottom. Topsoil particles (silt and sand) are many times larger than clay and will precipitate out of the water column better. But topsoil does have nutrients in it so if it is very fertile topsoil could add to nutrient problems.

My forage pond I essentially completely lined with crushed limestone that consists of rocks up to 1 inch all the way to ag lime fines with probably 10% ag lime. That pond is great. That is why I say it is almost impossible to get to much ag lime. Your pocket book will run out before you get too much applied. It has limestone 3" deep (called AB3 at the local quarry). If you put lime a foot deep you would just have a pond that acted like a water filled limestone quarry, ag lime simply being ground up limestone rock.

My old refurbished pond had clay bottom and was turbid. A couple of applications of ag lime from the bank and a years time cleared it.

Now hopefully someone will come along with some proper answers. That is just what I did. Others results could vary.

Take a look at this. Have soil tested by LSU for pond use. You could compare your farm soil as is - see below.

If you need lime put it in now.

Some additional information on pond liming.
Liming ponds

Quote from the above article:

"It is difficult to add too much agri­cultural limestone to a pond. At a pH of 8.3 or greater, calcium combines with carbonate to form limestone and drops out of solution. Limestone does not dissolve well in ponds where soil acidity has been neutralized and water pH has stabilized at or above 8.3"

"If high volumes of water regularly flush through a pond, the agricultural limestone, agricultural gypsum or calcium chloride that have been added can be washed out.  Often more than the recommended amount of limestone or gypsum is added so the materials will not have to be applied as often.  These chemicals will not cause problems in a pond if added at two or three times the calculated amount."