belkins456 to my knowledge there should be no problem with the alum that was applied last year. The only problem associated with alum applications that I'm aware of is the potential for a rapid pH change shortly after the application that could be lethal to the fish. Usually the alum application is done with sodium bicarbonate to offset the pH change. The other products I have seen in the past that are advertised to reduce phos. levels have alum and sodium bicarbonate as the ingredients. In my limited experience with them I have seen application rates for alum to be anywhere from 50lbs per acre foot to 150lbs per acre foot as determined by lab analysis. Kelly makes a great point with the algae growing on top of the pondweeds as I too have seen this happen. I have had a couple of ponds with significant amounts of algae growing on the coontail and once the coontail was dead the algae was greatly reduced. To my knowledge Aquashade was the only aquatic dye labeled by the EPA as an aquatic growth inhibitor so thats what I use and recommend. To get the full potential of the dye it should be applied early and fairly often. The recommended application rate is 1 gal per 4 acre feet of water. For my initial applition I like use 1.5-2times the recommended rate in the spring and follow up with the labeled rate every 4-6 weeks, depending on rainfall amounts, throughout the growing season and I have had quite a bit of success with control in water greater than 2ft deep. Even with the dye I do still see some algae and pondweeds growing around the edges in the 1-2ft deep range. Regarding the grass carp, the biologist recommended rate for control here in IL is 5 per surface acre for most situation but if your grass carp are older than 7 years old I have read that they may not be as effective at controlling growth. I dont remember where I've read or heard that so it may be an old wives tale that someone can clear up for us. For the water test I have used aquatic control and the test you would want would be the turbidity/nutrient analysis if you think the phos. levels are going to be high and if you are interested in having them figure out how much alum and sodium bicarbonate to apply. I believe the cost is somewhere between $85-100 for the test.