This is what I like to do a couple of times a week if I have time. If you are staying around Klong Prao, Kai Bae or Lonely beach then this is a nice paddle for anyone reasonably fit. All you need is a kayak, hat, sunscreen or inbuilt resistance to intense UV rays, 3 litres of water and about 3 hours free time. Bring a mask & snorkel and a sandwich or two if you want to make a day of it.
Point your kayak towards the furthest island, Koh Yuak, and away you go. Koh Yuak is mainly the destination for Thai groups on half day snorkelling trips, people taking their baby steps in the scuba diving world and people on the Sea Adventures catamaran ( should probably be a small ‘a’ for ‘adventures’ there.)
There isnt a lot there – a small beach and some great views. But the water is often very clear, there is coral and you will see fish – just sitting in the water near the beach and tapping the surface of the water with your fingers is enough to attract them.