Neptune tidal programme
We use it its cheap and ok, also do all the usual stuff like looking at tidal diamonds on charts and if you have the cash an almanac or tidal stream atlas, yes I know all extra cost, however, think about the amount of fuel you spent getting there and any air used that will need topping off at £2 - £2:50 a fill and books and paper dont seem all that bad value for money. Even better value for money is beer poured down other boaters necks who live in the area! worth its wait in gold.