well brass is 75 percent copper and the rest are zinc, heavy metal corrosion shouldnt relate much to the algae bloom, but usually algae consumes certain metals such as iron in the water, but i do not think it consumes copper by any chance. any free moving copper will attach to the CupriSorb, but copper as a heavy metal by anychance will still be in the silcone in your tank, i hope there will be less of a chance of destroying your corals, but CupriSorb will also attach other molecules besides copper so becareful on how much you use and the duration of time. 90percnet i trust seachem products to do what they do. I also wrote a huge thread on Hydrogen sulfide in MR. I dont know if you checked it out or not, but chris you really need to do some reasearch, silcated sand will harm your tank, if you used sugar silcated sand from homedepot your better off taking apart the tank and starting fresh. Skimmer will take care of your phytoplanktonic bloom, these creatures use light as a source to generate a glucose and it's the basic building block of life. But please go read for sake of your animals. Not saying your a bad reefer, but a reefer needs to learn on his own to form his own opinion about his tank. take a look at my sig.