A relatively cheap and common form of indoor lighting in Twowi households are slime lanterns; strains of bioluminescent microbes native to certain freshwater wetland environments. Centuries of cultivation have given rise to cultures that will glow brightly for many hours on relatively little feed (a mix of powdered pond scum and clay minerals). Many strains are unique to individual clans, and a clan’s reserve of ‘moonblood’ is regarded as a treasured family heirloom.
Care of slime lanterns is fairly simple: when light is needed, measure the needed ration of feed, mix it into the culture, and wait a few minutes. More feed will favor a brighter light over time as the microbes rapidly reproduce, but will ultimately dim as the original batch dies and clouds the water faster than their nutrients can be recycled. Good upkeep requires keeping the jar topped off with water and regular water changes.
In summer, when the light from the sun is almost constant and ship’s prism type indoor lights are more reliable, larger slime lanterns are emptied and a reserve of the mother culture is put into cold storage to save on feed.
This is an old post from my Patreon, decided to switch it to public and share here because it’s one of my favorite tidbits I’ve come up with in the last few years.