I have never even tried to use pine bark (I assume that's the same as fines?). If it works well, it sure would be way, way less expensive that the Douglas fir bark I use. I don't have any aquariums, so mine just get city water dosed with low concentrations of fertilizer every few days. Other than on cloudy days, I mist/spray all my plants every other day or so. Some of the mounted ones dry out more quickly (though I use mesh-pots almost exclusively for my potted orchids), so I might spray them daily.
Because of my flooring, the humidity stays pretty high in my greenhouses. But I also run 2-3 fans in each greenhouse. During the cool/cold months, the fans come on around 10:00 AM and turn off around 4:00 PM. As the weather warms, the fans will run longer. If anything, because I don't heavily water very often during the colder months, and certainly don't water during cold, cloudy days, I probably keep my orchids on the dry side. Of course, all the fans help. I don't know if my keeping them somewhat dry is good or bad. I assume my plants won't grow as fast as they would IF I had a really controlled environment (like the truly commercial growers have) and I probably get more "wrinkling" of the pseudobulbs doing this, but for better or for worse, that's just the way I grow mine.