Thanks for the replies. I don't think that I have any crayfish. There are lots of Bullfrogs and we always had lots of big tadpoles, (but there seem to be fewer this year) I know that there are leeches (which I wish the Bass would eat)
I am just hoping that the Bass are still there, even tho I have never seen them.
Water visability is only about 30 inches. I suspect that this is due to the goldfish stirring up the bottom (which is mud)