First, an updated graph:
I did get lazy and stop logging the RH, but it has leveled out and is staying consistently between 68% and 71%RH. This could be a result of the tea having absorbed it's proper amount of moisture. This could also stem from my not opening it every couple hours to check the humidity, like I was doing before. Lastly, it could be from having a greater volume of water, which I don't think is the case because all the vesicles holding the water still have the same surface area as before.
I've been swapping out water every two weeks, cleaning the dishes with soap, and rinsing them very well before putting them back in. The cleaning is keeping the water from growing any mold, and the hefty rinsing is to keep all the odor of the soap away from the tea. I've been striving to keep the cabinet clean. This means washing hands before handling all puerh so as not to contaminate them.
I acted on commenter Stephane's advice, who suggested that I store a chunk of the puerh on a nearby shelf. Down the road, this will hopefully determine differences between the two storages. The victim of this experiment is a 2004 Xiaguan tuocha that I picked up from Puerhshop last fall.
I wrapped the pieces in tissue paper to best keep all other storage aspects identical.
I decided to chop a chunk off of one of my purple leaf cakes. This, I thought, was a good idea because purple leaf puerh is fairly new to the market, so it's aging process is widely unknown. SO in the interest of scientific advancement....
I broke my knife. Damn. Next puerhshop order, I'll snatch the Pu-erh Sacrificial Death Knife. For now, I'll have to find a replacement. I still managed to get a chunk of purple out. This new experiment box has gone onto the top shelf, just above the pu-erh chamber. It now contains 1 Chunk 2007 Purple Leaf, 1 Chunk 2004 Xiaguan, and 1 mini-tuocha for good spirits. Some time after this picture, the humidity is reading at 52%, and still dropping.
I must admit that my hygrometer might be reading a bit low. I performed a shifty experiment that is supposed to determine how far off the mark a hygrometer is, and mine read 8%RH below. Well, I don't think this is saying much yet as there are too many factors that could have resulted in this bad reading. I'll try it a few more times and see how it goes.
Now that experiment is in order. I want to show you my other invention for puerh drinkers.
That's it. A can to collect pu-erh leaves. Please, save the Lemelson-MIT award, really. ...Ah, the meaning of the can. Well, there were too many times when I was done breaking up some puerh, and had a smathering of crumblings and dust left over. I also found that after I finished my samples, I would be left with a few chunks which weren't enough to make a pot. I decided to stop throwing them out the window, and to collect them. JF is doing something similar, I believe he's wet-storing them. These are going to stay dry (well, in my enlosure). This will probably benefit my other teas in one way. That is, when I finish an expensive aged puerh sample, I can keep some crumblings in this can. I hope this will serve to more quickly introduce all the friendly bacteria that develops on puerh over time.
Check back in a few years to see how things are developing!