Astronomy & Physical Aspects
Near-perfectly balanced in its orbit, Scaich or TRAPPIST-1g is a cold world with a near perfect circular orbit and just barely within the habitable zone of TRAPPIST-1. With vast reserves of algae in its waters from a careless initial survey team, the invasive species quickly populated the global ocean's surface, killing off the marine life underneath to produce a green sea, the landmasses and clouds being the only source of a different colour on the planet.
Much like the other prospective sites in the system there is no permanent residence. The planet is still periodically chosen as a haulage site from Ulm due to the algae being a prospective food source and is regularly collected for tests and analysis on its survival abilities on a new planet. Any prospective colony however would need significant infrastructure, though would likely be a mining colony due to the surveys showing a significant amount of titanium beneath the waves and islands.
Points of Interest
Native flora and fauna
There is only one form of life on this planet above that of microbe which would be Earth originating algae. One of the initial survey teams not being properly sterilized, the planet suffered from significant contamination which spread across the ocean and starved the marine life of oxygen in a matter of years, leaving only skeletons at the bottom of its deepest and darkest trenches.