Hi Martin and welcome to the forum!

I am not a pro but it sounds like from your description of the brown layer moving from the bottom to the top that you are witnessing what is called a pond turn over. I suspect the frequent applications of straw is contributing organic material to the "brown layer" as it falls to the bottom and begins to decay. If that is the case, then bottom aeration should help. I will leave it to the pros here to give you more informed thoughts and advice.

Good luck and very happy to see you on the forum!

Bill D.

Last edited by Bill D.; 01/26/16 08:16 PM.

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