PXK pergium reactor

A PXK pergium reactor was a nuclear energy source used in the 23rd century. In 2267, it was used in the Janus VI pergium mining colony to power all of the life support systems there.

In that year, the silicon-based lifeform known as a "Horta" stole the main circulating pump from the Janus VI reactor, an action which would cause the reactor to go supercritical. Captain Kirk asked Scotty if they had any replacement parts on board the Enterprise, but Scotty responded that the reactor had been out-of-date for roughly 30 years, forcing him to construct a makeshift replacement pump.

Eventually, Spock was able to make contact with the Horta via mind meld, and the Horta agreed to return the circulating pump. 

PXK-Pergiumreaktor