Over the years I've used a lot of different brands of nectar for the Hummingbirds.  Perky Pet makes a very good product that is compatible with the Hummers.  This is the first time I have purchased the powdered nectar, however....mostly used the liquid concentrate. Well, it is so simple to mix with water (this one turns red)and it dissolves quickly, and the birds love it!  My current feeder only holds 1 cup, so I use a glass 1 cup measure, add 3 Tablespoons powder, and add water to the 1 cup line = easy peasy! The amounts are on the back of the package.  What I like best about this "instant" nectar is that there is no need to boil it, like when you mix up a homemade batch using sugar and water.  No waiting for it to cool for the birds to enjoy, it's ready now!