Hey guys I’m new hear so sorry if it’s been asked and I can’t find the thread. Been running my tank for a while now have slowly added fish and inverts, currently have some snails hermits two star fish a crab a shrimp two other fish and then a yellow watchman and a pistol shrimp. As add more to the tank I really enjoy watching and seeing how those two pair up and stay together I find it very cool and intriguing so the question is… is there any other pairs of say fish and inverts or maybe two inverts or two different fish that will pair up and bond like these two do? Or is it possible to add another pair of these two to the tank?