One besser block at a time is all it took me i built a niffty little reef in a quiet river system (far north coast) i't only took one week and it wa the new bream spot. not to menntion the jacks and cod that hanged around at night made great fun until a storm came along and covered it or washed it away, forty gallon dums hallowed out and tied together and weighed down make good school dew holes. sshhh.... Hahahaah. but i have given up now and feel its cheating or polluting.