mercury fillings and hydrogen peroxide

Hey guys, First off, I'd like to thank everyone who participates in this website: the information has proved to be invaluable to me, and I make it a religious practice to educate instead of medicate in my daily life. Now, to clean my teeth, I use a combination of sea salt, baking soda and hydrogen peroxide. Someone recently told me that the peroxide is the WORST thing for someone who has mercury fillings, which I have alot of. Is this true, and if so, what exactly happens? I am planning to replace them, but $$$ is extremely tight. Also, I was also told that all my liver flushing, bowel cleanses and fasts are doing absolutely no good because of the mercury. True/False? Do you know of any supplements/herbs that help with heavy metal detox? I've been using lipoic acid for some time now. Thank you. Love and Peace.