This new heron deterrent utilises bright lights, sound and a laser to scare predators away from your fish. The ultimate detterent this product was voted \'best in show\' in October 2017 at the Uk\'s biggest aquatic exhibition. Bright goldfish or koi will always attract herons. In a clear pond they are easy for a hungry heron to pick up from far above. In spring they need to feed their young, in summer to feed themselves and in autumn when alternative food is scarce.