Small backstory and description of inhabitants: I have a ~50 gallon reef, no sump, that has been running for about 4 years. I started up with 2 ocellaris clowns, 1 ecsenius bicolor and 1 stenopus hispidus shrimp. All of these 4 learned to live together and were the only ones lasting; the shrimp has been hunting the blenny since the beginning but the blenny learned to keep distance. Sadly, about a year ago we moved the tank and had all live rock placed in a tub, blenny hid in a rock and jumped out of the rockbucket and went floorsurfing. During the 4 years the tank has been running we have had several fish, all of which have mysteriously died. We have now seen it confirmed that the female clownfish beats up anything that comes into the tank (no big surprise) but also that the shrimp goes hunting anything that is slow/peaceful enough or goes to rest in the wrong place in the wrong time. She catches fully healthy fish, or the fish that have been beaten up by our female clown and are thus weakened. This means we have a reef with only 2 fish, and major desire for a few more species. You see my problem, of course. I have been thinking and reading and come up with a couple of possible solutions, or at least things to try to be able to introduce new fish to our murdertank and would be happy to hear your thoughts on it, or other tips regarding this issue. Sorry about the lenght of the thread, but I hope all info gets across well. And if someone have had the same problem with killer shrimp and killerclowns and succeeded in introducing new (mostly peaceful) fish I am very glad to hear how you did it and any other clever tricks you could recommend! (NOTE: Before any introduction all fish and shrimp will be extra well fed. I will also ensure they remain extra fed the coming days to hopefully make them a bit less grumpy against the newcomers. The introduction may or may not be combined with a mirror to make the clowns focus on themselves instead.) IDEA 1A: Lights out, dim lamp next to the tank. ------------------------------------------- WHY THIS MIGHT WORK: In the dark, new fish will be harder to find, but they will have a harder time finding caves and hiding places in the dark. A dim light from outside the tank might make them harder to see, but still make them able to find the hidingspots. I will also be able to see what happens. IDEA 1B: Same lighting level, combined with some rockwork slightly rearranged + sandbed slightly stirred to make the tank a bit more foggy and different. This might disorient the clowns and cut viewdistance, but still be bright and clear enough for new fish to learn the tank cave locations. IDEA 2: Complete rescaping. ------------------------------------------ WHY THIS MIGHT WORK: Territories need to be resettled, new fish might get a chance to establish their own caves while clowns and shrimp look around the new layout to find the best new spots for them. IDEA 3: Putting clowns and shrimp in QT tank for a time while new fish is introduced to DT. (Catching clowns might require a trap or a complete rescape of the tank.) ------------------------------------------ WHY THIS MIGHT WORK: The new fish gets the entire tank to themselves to settle in. The clowns and the shrimp will hopefully "forget" before they are put back in, and the new fish will know the area well. If the new fish are there before the clowns, the clowns may be more accepting and keep other fish in account when they reestablish territories. These are the main ideas I have thought of. If I can break up the territory, the clownfish should hopefully be peaceful enough to accept new fish while she reestablishes her place. The shrimp on the other hand can be more tricky, as she can more easily ambush hiding or sleeping fish and seem less territorial and more "on the hunt". Would very much like to hear your thoughts and experiences!