With all the discussion about anchor type and anchor size, the most important aspect was not discussed. That is the length of the anchor rode. A 10:1 ratio of water depth to anchor rode length is the optimum. Ten foot water depth = 100 foot rode. But this is the ideal condition where you have unlimited swinging room. As the rode gets shorter because of nearby anchored boats, then you need more chain. The whole object is to keep the pull on the anchor as horizontal as possible. That allows the anchor to dig deeper. Deeper = more security. The chain lies on the bottom and keeps the pull on the anchor horizontal. With a short rode, the influence of tidal range, and wakes, will cause a vertical pull on the anchor stock, tearing the anchor away from it's hold on the bottom. At that point, you are drifting through the anchorage. Connie