It’s the yin-yang, the perennial agony after the ecstasy for science fiction fans.Like “Farscape” and “Angel” fans before them, once again, fans are mourning lost favorites or scrambling to save those in dire trouble.The TV season has begun claiming its scifi victims. It’s the pain we fans seemingly must endure year after year.ABC has canceled “Night Stalker,” the second time, as SciFi Wire noted, that the network has killed a series about reporter Carl Kolchak and his pursuit of the supernatural.Just six episodes of “Night Stalker,” an update of the 1974 series, “Kolchak: The Night Stalker,” have aired. The original show lasted just one season, from 1974-’75.The new series, on Thursday nights opposite powerhouses “CSI” and “The Apprentice,” struggled in the ratings, falling as low as under …