A point which has not been mentioned is that you should not just bung it over the side. An anchor needs to be set by paying out approx. 3x and backing down under low power, down wind, until it holds firmly, then pay out the remaining scope. Also, there is no such thing as too much chain and always use twisted nylon. Personally I always carry a spare second anchor and have had need to use it many times. You can buy aluminioum achors also, but they are expensive. It is not the weight that does the work but the shape/surface area.
Running around like a head with it's chicken cut off.