I usually use a 5% brine (50g of fine salt for every litre of water). You need enough to fully cover the fish or meat and a container big enough to put it in. For 3 litres of brine, heat up 200ml water in a small pot and add 150g fine salt. Stir until the salt has fully dissolved, then pour it into your container. Add the remaining 2.8 litres of water and stir to mix, then submerge whatever you are brining. Fish only needs to brine for 4 to 12 minutes depending on how thick it is. If you’re brining meat, put it in the fridge and leave it overnight or for 12 hours. Pat dry with some kitchen towel – there’s no need to rinse it – then put into the fridge for a couple of hours to dry.