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.
For other people and other uses, see Dido (disambiguation). Aeneas recounting the Trojan War to Dido, a painting by Pierre-Narcisse GuÃ©rin. This scene is taken from Virgil's Aeneid, where Dido falls in love with, only to be left by, the Trojan hero Aeneas.