My real purpose of getting them is to "prepare" my tank for the white jardini and "spotted" rtc that'll be coming this following Saturday. The pooping will mean the biological waste will be high, which promotes the growth of beneficial bacterias, which means when I introduce the new fishes, there won't be any sudden spike on ammonia or nitrite. Most mature aquariums don't have that problem, but I recently removed all of the sand substrate in my tank, which I depleted a good amount of bacteria in my tank, making the water chemistry unstable for several days.