They reproduced very fast in my fishless frag tank but collecting them was difficult and impractical. the best way is to grow chaeto in sump/fuge and every few days take chaeto out and shake it in display water. A couple pods will abandon ship! Only problems with this is the chaeto shaking in water can release some stuff, dirt, or pooh that got stuck in it. I usually just pick up some live brine or black worms at LFS so the fish can get a nice live treat