It's tiny, about 1-2 teaspoons. I use a 1 litre mix of boiling water to 2 litres cold from the tap and then put the 2 teaspoons in and mix well until the water goes purple. Then put the barrels in for 30 minutes swooshing the liquid around every 10 minutes.

I used a window flower box (plastic) for the container. Also make sure you bung the barrel ends up. I used wine bottle corks.

Cheers
T

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