When you're not using your tea lights, it can be very easy for them to become dusty in a cupboard somewhere. While this isn't a major issue if you're employing them for personal use, it can affect your sales and the reputation of your business if you choose to sell them on to consumers. To avoid this, try and keep your candles in a waterproof plastic container with a lid. This will prevent dust and debris from developing on the top. It's also a good idea to store your candles in a cool, dry place to avoid any temperature changes to the wax.