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 was born at St Mary Abbots hospital in Kensington, London, on Christmas Day 1971. On her birth certificate, her name was registered as Florian Cloud de Bounevialle Armstrong. Because she was born on Christmas Day, she also celebrates an official birthday on 25 June, following the example of Paddington Bear.