i waited until they were completly free swimming.. im not sure exactly how old they are. i found them as fresh wigglers and that has been about 3 days ago. i deff think that syphoning is they way to go if your moving them into a different tank...that way they arent exposed to air and its easier to catch them...netting them would have been a nightmare in a 150. im going to get micro worms and brine shrimp today...its so crazy how many there are....i kept saying theres millions...lol...