I started having floaters in 2001 one month after I was exposed to mercury vapor in my dentist's office. When I started taking DMSA to pull the mercury out of my body, after I had my mercury fillings safely removed, I could "feel" the mercury being pulled out of my my eyeballs.
I am still using DMSA to get the mercury out of my brain, but I no longer am bothered with mercury in my eyes now.
For those who doubt heavy metal toxicity in the eyes, if you check out the eye section in the reference book they use at GNC vitamin stores, you will find they list supplements that pull heavy metals out of the eyes. The book is called Nutritional Healing or something similiar. I can't recall exactly, but it is a very good alternative health book.
If your floaters are caused by heavy metals, you need to get rid of the source of the heavy metals. Check out my website for how to have mercury safely removed from your teeth. Regular dentists are not trained in the safe removal of mercury fillings. And do not take the flu vaccine. It is loaded with thimerosal (mercury).