The birds in my garden go mad for this !
It's a mix of white millet, red millet, panicum millet, japanese millet, linseed, black rape seed, nyjer seed and naked oats.
I noticed during the summer that the house sparrows prefer this to anything else I put out. I have 30-40 house sparrows in my garden every day

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I usually mix some budgie tonic, a little general wild bird mix and some rolled oats and fill 2 feeders with it. They are always the first feeders to be emptied. The other 2 tube feeders I have just have general wild bird mix in them. They are still nearly full from Thursday, while the 2 budgie tonic/rolled oats ones have had to be filled TWICE

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Birds which use these feeders are house sparrows, greenfinch, goldfinch, siskins, blue tits, coal tits, great tits, starlings and even jackdaws. I've also seen chaffinches and a robin eating from these feeders.
I usually scatter some on the ground too, along with the general mix, and all of the birds eat this too. It's hilarious watching a rook, collared dove or wood pigeon picking up the tiny seeds

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All of the ground feeding birds eat it too. I've now got a female brambling coming every day, and for the first time, a reed bunting.
I have more birds coming to my garden now since I started feeding budgie tonic, than I ever did with other wild bird mixes. It's even more popular than sunflower hearts were.
I've just bought a 20kg bag from my local pet shop. It cost £22.49