Corals have a variety of feeding methods they utilize in order to gather food from their environment. Most of the time, short tentacles emerge from a coral at nighttime, giving it a much more extended reach. Certain species have what are called sweeper tentacles, which are significantly longer than the normal tentacles and can pack a powerful punch. These tentacles can sting and kill other corals, making their placement in the aquarium very important to make sure there are no territory wars. Typically, corals of the LPS variety have these long sweeper tentacles, but other corals can have them as well. So, it’s important to know which corals do what, and move them around the aquarium accordingly.