Had to clean some valonia off two heater guards (that were going back into the tank) plus a powerhead I was putting into storage. All had serious coraline algae on them. Soaked for all parts with coraline on them in 100% white vinegar for 6 to 8 hours, then easily toothbrushed off the coraline. Rinsed well in tapwater. Did not see any valonia left on the heater guards either
