Go to the fountain with GREEN WATER in it,get up there,blow up that brick,become minish,get there,and scoop some up in your bottle

Go 2 mt. crenels base and bring an empty bottle. go 2 the green spot on ur map. u can get up there by pouring water on the seedling vine and climb up it. go around the platform ang place a bomb inbetween the 2 posts there. go through the tunnel and up the latter. then shrink using the rock there and go through the crack. there's were the water is. u swipe the bottle through the water and ur set.