So I have a local lake it's a resevor lake no real current unless it's raining and then not real current [censored] the water is let out from the toon of the bottom of a dam outlet. So bottom is never cleaned out. Lake is super deep in spots like 75 let is 25 plus. Most lakes here are like fish bowls. Few area of shallow but mostly cliffs. Anyway lately the water has become the clearest I've ever seen it but bottom has so much old stuff on it you don't see the bottom like clean lakes. You can see 5-8 ft but that's prolly the end. The bottom is all black lots of old leafs and such. Not only is the water clear I've noticed it's starting to get a brown tint kind of like tea. Anyone know the cause of that? When lakes that deep turnover do they stink? I've seen green sponge stuff starting to float I assumed that was turnover but someone says no deep lake like that won't turn over. Doesn't seem right to me.

If you are saying that you have been told that deeper lakes do not turn over then no that is not true. Actually it's smaller shallow lakes/ponds that have no noticible "turn over" when surface temps drop below the deeper water temps and that heavier cold water "falls" and the lighter warmer deep water below the thermocline rises to the surface. It often brings up the "stuff" you are describing along with a foul smell. Usually more pronounced on deeper lakes.