Take an old pair of your wife's panty hose and cut it so that you can tie one end, fill with fish food, then tie the other end. The fish food will last a long time in a mushy state. One pair of panty hose will make enough food pouches to last several years. You can actually untie one end and rinse the pouch out and re-use it. I have no idea how I came up with this idea, but it works very well.