I'm 33 years old and if my mother were still alive (god bless her), she would knock me across the room if I attempted to talk to her like that!! I think Dragonscales idea is good, but I'd go about it in a totally different way. Ask your mother if you can have a talk. Tell her how you feel about what she's doing. Have this forum printed out to show her, and maybe any other pertinent information you can find to show her. Ask her why she feels she needs goldfish to eat the larvae when there are so many different ways to take care of it. Hopefully she'll listen to what you have to say. She may not agree with you, but maybe you can come up with some kind of understanding.