Re: anchor chains or not
6' of chain should be plenty. The chain absorbs the shock of the boat tugging on the anchor due to wind/waves. I would also the proper amount of scope in order to keep the anchor set, especially in soft bottoms. We have 100' foot of line on our anchor rode, and use 50' of it when anchoring in 10-15 foot of water. It's not quite 7 to 1 ratio, but water/wind conditions dictate what scope will be necessary in order to hold your position. If I'm in a still cove, I can drop a mushroom anchor on our jetski and be just fine. If I'm in an area with lots of wind and/or waves, the fluke anchor with enough rode out to provide higher scope is necessary.