So I've eventually constructed my first bog planter. picked up a lot of ideas from the ones on the forum. went for a plastic container made to look like a wooden barrel.
Drilled a hole in the side right near the bottom to fit a drain of tap.
Also drilled some holes all the way round just below the first band on the planter these are for over flow in case of a heavy down pour.
Made a reservoir and a water gauge from a Chinese takeaway tub and some plastic