I am trying to get a better understanding of phosphate mitigation treatments. It seems the more I learn, the more I need to learn. Could someone please explain to me the difference in using alum versus bentonite/lanthanum (Sepro's EutroSorb Products)? I had a suggestion for a "flock and lock" program" which would be alum followed by the EutroSorb. I'm hearing the term "sediment reflux" in relationship to phosphates being rereleased back into the water table. I'm struggling to understand if phosphate will unbind from alum. Does anyone have a link to an article that can give me a better understanding of this entire process?

I'd appreciate any clarification or information anyone can pass along. Thanks!