Need to make and keep a kill hole in the shallows of my new property. As well as keep plants from invading my channel.

Thanks in advance MT

If your speaking of the pellets for killing lake weeds, yes I have used them in a couple different locations. They do work. However the type of bottom has a great impact on the result. If you have a hard sand bottom and the pellets dissolve on top of it as they should it's great. If you have any sort of soft bottom the pellets settle down in, as they dissolve they do not dissipate outwards nearly as much so they do not perform well.

Osky

Michigan, fish hatchery worker here. Copper sulfate pellets and liquid solutions are a go to around here for pond weeds. Diquat is also something new we have been testing, should work equally as copper, at least time will tell. Not much likes copper- fish, plants, algae, mussels, etc. will die quick if their is enough. Just be careful not to overdue it and I'm sure your kill hole will be looking good enough to be mistaken for a private swimming pool

X2 on the Copper Sulfate. Just be careful and follow the ratio directions. I accidentally killed a dozen of my big catfish and about twice that many "big" hybrid bluegill a few years ago treating alga. Been using barley straw the last 2 years with great success.
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The water body is 150+ acres.

The kill hole would be in about 18" of water with 2 feet of old vegetation over sand. Thinking may have to find a way to push the crap off the sand

The channel has the same on the edges but is sand down the middle but the lily pad are encroaching in to it

Up here dragging an old bed spring works wonders for cleaning the bottom. Others use a sludge pump sucking out of the same lake and the discharge end wired to a concrete block which they move as needed. Blows the bottom pretty darn clean.

Osky