Descale
To remove the scales from fish before cooking, this process is also referred to as scaling. Some fish have a layer of tough scales that need to be removed before cooking. This can be done using a specialist fish scaler (similar to a small grater) or a serrated knife, it is quite a messy job so if possible do it outside or in a polythene bag or alternatively ask the fishmonger at Waitrose to scale fish for you.