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For those who maintain a dunder pit, do you add anything to the dunder pit while waiting for it to do its “thing”??

I’ve heard of some distillers throwing spoiled bananas, banana peels, cut up rotten apple pieces, zest from oranges, limes, lemons, cut up rotten pear pieces, other various spoiling/rotten fruit items, etc. etc. into their dunder pits, and I was just wondering what others on this forum have experimented with...

And, I’m not talking about goat heads and dead bodies like they do in the Caribbean…lol.

I think of it as "managing" a pit, not adding ingredients.
Do you want to ensure certain microbes are active? Well then you need to innoculate your pit with something. Soil, potatoes, swiss cheese, yogurt, etc.
Do you want to keep the bacteria active? Then you need to manage the pH of your pit, adding lime/shells/chalk/marl whatever to keep the pH in the 5.5-ish range.
Are you feeding your pit enough? Yeast for sure. But since most of us don't have skimmings and cane trash and whatnot, some carbohydrates from time to time might make sense.

Personally I would never add citrus, nor add fruit unless it was simply to capture some microbes that might be growing on it. It's easy enough to flavor rum directly if that's the goal

Thanks for the feedback zapata!! Yeah, the pH is below 5…about 4.8, I’ve added some yogurt to inoculated, and I have the pit open to the air to catch any airborne yeast. This is my first time trying this, so I’ll see what happens…

In mine I put:

backset, pot ale, whatever you want to call it, left overs from a stripping run

1#/gallon sugar
several handfuls of oyster shells

bottle of sour beer: hopefully to product some acetic acid

swiss cheese: hopefully to produce propionic acid

malted grain: hopefully to produce lactic acid

pineapple, cherry, limes, orange?: citric acid, fruit flavor

I just started a big batch, will be adding some of this "dunder" to the stripping and spirit runs.

I have no way of really judging which acids are or are not present, I can guess by smelling it, and I've read the bacteria that produces the propionic acid is pretty fagile so I'm guessing that one probably did not survive.

Acetobacter and lacto bacterias tend to be pretty strong so I probably have mostly acetic acid, maybe some lactic acid, and a little citric acid.

There's only 5 gallons of dunder for 80 gallons of wash, so about 6% dunder to wash ratio. I'm going to take notes on how much etc.. in each run, if I find anything interesting I'll post about it, if you don't hear from me then nothing interesting happened.

I had a pretty standard pit going with backset and some sugar. Threw in some live culture yogurt and did not notice any changes. It is a fight to keep the pH above 4. Added a dollop of molasses and everything changed. Started getting that funky cowpie smell I associate with Bret. I don't notice anything different with the final product but I don't have a vert sensitive palate.