I am a first time purchaser of mashua tubers and am having difficulty with a fungus problem. Originally I received 5 tubers and a fungus quickly started growing on them. Acting I removed the portions of the tuber infected with a buffer and planted in newly purchased top soil; however, the fungus has reappeared and now there isn’t much left to save. How do I battle this what should I do in the future? It has only been a week and a half since I received my package.