Judge the tank you own by its footprint and the adult size of each cichlid, not by the juveniles in the shop tank. Peaceful combinations are built on space, territory, and temperament working together. A mix that looks calm at two inches long can fall apart once the fish mature, claim caves, and start defending them.
Start With Footprint and Adult Size
Measure the length and depth of the tank, because cichlids claim floor space and cave sites rather than open water. Look up the adult length of every species on your list and picture those fish, at that size, sharing the footprint you measured. Long tanks usually give territorial fish more room to spread out than tall tanks of the same volume. If two species on your list both need the same cave-filled bottom area, the honest answer is often to choose one of them. Stocking for the fish you hope they stay, rather than the adults they become, is where many conflicts begin.
Divide the Tank Into Zones
Build the group around different zones. Pair bottom-oriented species with fish that hold mid-water or open areas, so each fish can feed, rest, and retreat without crossing another fish's defended patch all day. Match confidence as carefully as size. A bold species that rushes every feeding will slowly starve a shy species even without open fighting, while two equally pushy species may contest the same cave daily. Keep only one male of each territorial species, because rival males of the same kind are a common trigger for persistent chasing. Groups of a single species need enough members, and enough space, that no one fish absorbs all the attention.
Give Every Fish an Exit
Provide more caves, rock gaps, and sight breaks than there are fish. A chased fish that can break the line of sight usually escapes, while a chased fish in an open tank simply gets followed. Arrange rockwork so territories have gaps between them rather than one continuous fortress with a single entrance. Spread food across two or three spots at feeding time so subordinate fish can eat away from the dominant one. Watch fins, appetite, and hiding time during the first weeks. A fish that stops emerging for food is giving you information, not settling in quietly.
Add Fish in a Safer Order
Add the least territorial species first where your plan allows, so those fish learn the caves and feeding spots before bolder tankmates arrive. Rearranging rockwork just before a new arrival can soften an established fish's claim, because the old territory boundaries disappear. Quarantine new fish in a separate tank before they join the group, and use that time to confirm that each fish is eating well. Introduce one change at a time. Adding several species on the same day makes it impossible to tell which addition caused a problem.
Keep a Separation Plan Ready
Accept before you buy that an individual fish may not fit, however careful the plan was. Keep a spare tank, a divider, or an agreed return or rehoming route ready, and act early if one fish is losing weight, hiding constantly, or carrying repeated fin damage. Separating a fish promptly protects the whole group and gives the removed fish a fair chance elsewhere. Keep brief notes on which fish was moved, when the chasing began, and what else changed in the tank during the days beforehand. KinsLe's Transferrable Profiles supports that move, since the fish's species, origin, diet, and behaviour notes can travel with it to the next keeper instead of being reconstructed from memory.