The study from Phoslock seems rather biased, saying Alum is pH driven while Phoslock isn't, yet going on to say "optimal" in a 6-9 pH....sounds pH driven just like Alum to me... Since I happen to know that alum is also "optimal" at slightly a lower pH range, yet works outside those ranges...that comparison alone is misleading, if not intentionally false. As far as toxicity, pH has to drop to 5.4 before aluminum dissolves and can become toxic...a level that is lethal to most fish anyway, so rather irrelevant in a sport-fish setting.
Other things that stood out to me were words like may, or might when referring to phoslock and not with alum in binding phosphorous permanently and becoming a barrier to sediment based phosphorous...again, very misleading to most casual readers looking for solutions to high levels of phosphorous.
Alum, (AlSO4 or Aluminum Sulfate) is classified as a GCS (Generally Considered Safe) chemical by the FDA and for years, was used in virtually every municipal water supply in the world. A rash of reports once claiming links to brain disorders, like alzhiemers, have all been debunked and proved false.
I think Phoslock is a product that works, yet not as well, permanently, or at a nearly the cost-effective price as Alum.
For me, the report linked to is a prime example of "outcome based research"...stating facts in a way that only support a desired conclusion while ignoring, or trying to minimize, facts that could oppose the desired conclusion.
Last edited by Rainman; 04/03/15 04:52 PM.
