most likely the bulbs were not kept at stable temps during shipping and transport,i.e. very hot and dry one place then humid next then cold etc.by the time they get to the retailer they are in poor shape and even poorer by the time the consumer gets them.you get them home,throw them in full submersion,and a host of things happen.usually mold,fungus,and any other form of rot.visually inspect the bulbs before you put them in.no softness,discoloration,pests,etc.i have grown tons of beautiful aponogeton sp. from those walmart bulb kits.good luck.