This is my oil production rig. I have around 30 or so fish traps in the bottom, and 24 fluid presses up top. Out of the 30 or so fish traps, I only had 1 that was not regularly producing fish and had to dismantle it. In a morning harvest, I get around 2500 oil from fish spread evenly through the presses. I use this for all my fuel needs, and provide free oil to anyone on my server who wants it. It can be used in furnaces, stoves, campfires, and alchemy cauldrons. I use bark only for the dryer and hide when I need it, and I can save all my coal to turn into tar through another fluid press.
Soon I will be adding shellfish traps and cook stations nearby to harvest ichor, and any fish that go bad go into my compost heap at my main base nearby. The waste has been relatively small with this setup, about 24 fish over the entire morning harvest. At the end of the night I do another harvest and get roughly the same amount.