I do, and here's how I do it. I take the old potting soil, put it in a 3 gallon pot, and pour a kettle of boiling water through to kill it, then I mix it half and half with new potting soil. Things grow very well in this, and I've never had any root rot problems from the old soil.
Didymo (Didymosphenia geminata), also known as rock snot, is a non-native invasive microscopic algae (diatom) that can produce large amounts of stalk material to form thick brown mats on stream bottoms.
Dido, also called Elissa, in Greek legend, the reputed founder of Carthage, daughter of the Tyrian king Mutto (or Belus), and wife of Sychaeus (or Acerbas). Her husband having been slain by her brother Pygmalion, Dido fled to the coast of Africa where she purchased from a local chieftain, Iarbas, a piece of land on which she founded Carthage. The city soon prospered, and Iarbas sought Didoâs hand in marriage.