wow! Oh, okay.. that kind of nutrient. I don't call that nutrient cuz it don't benefit my tank... lol. Thank you for clearing that up. I was like why do I wanna feed that stuff too! >>>>> what Tiger says. >>>>>> Agreed. I usually have low to no levels of NH3-4,NO2,NO3,PO3-4... I was using it for preventitive maintenance for when I am out of the country and can't get to my tank. I don't want to throw a clam in there before I leave and hope it works. (I am unfamiliar with clam taking that kind of "nutrient" out of the water. I have actually heard that Xenia like "dirty" tanks so you may be right about them taking stuff out of the water. THAT IS NOT A HIT TOWARD YOUR TANK BEING DIRTY. So please don't take offense to it.