Hit'em as soon as they move into a holding spot. They are usually super agressive during the sorting out of pecking order period. You have to be quick as this period may last(usually) less than a minute....after that they settle down into nonbiting mode. My theory about black yarn working so well is based on several biological items: 1) what colors do you see in a silvers or kings mouth area?...Black & White; 2) salmon communicate by displaying these colors to each other and the display is territorial. Notice the flashes of black & white we see from the mouthes of an active school of silver that just moved into a hole.
All of these displays involve anger and aggressiveness. Would love to have some black & white vibraxes.

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