sour milk smelling pond!

[newtlover]

I have a new -well 2 month old pond, which is filled with rainwater and has a logpile next to it. We put pond weed and snails from a local pond in a fortnight ago. It's full of some sort of larvae and water is blackish. Its under a pear tree, but not in deep shade- some fruit has fallen in but I fish it out. Water smells strongly of sour milk
what to do???
have googled to no avail- most pond problems seem to relate to algae.

help?

we have a pond too and it doesnt usually smell, (although the dog stinks when he jumps in it). The only think I can think of is maybe the smell is to do with the wood pile or its just because the pond is relatively new and things are still settling.

this is what I am hoping- the woodpile is reccommended for wildlife- how old is your pond?