Those are anti-biotics that will kill the cyanobacteria, similar to the erythromycin that I mentioned before. But as has been stated before, this should only be used as a last resort AFTER you have tried every thing else. The best advice I can give you right now, is to perform 10% weekly water changes, while manually siphoning off the cyano from the tank, until your get it under control. Make sure you are not overfeeding your fish. I dont know much about your setup or how much money you are willing to put into your aquarium, but your tank would greatly benefit from better filtration, such as a protein skimmer, and using RO/DI water for mixing salt and top offs.