Posted: 07/02/2014 at 16:12
If you are using old blue plastic chemical containers, they have one or two plug holes in the lid. Cut the lid off just below the rim and turn it over. Remove the plug, place the lid on the container and it will fill. You don't need to cover it with anything as the plug hole is slightly high so only water goes in.
When the container is full you can just replace the plug in the plug-hole. If the water is always covered the water will stay clear and sweet from year to year.