Do you have a liquid test kit? Without it, there is no way to be sure if your aquarium is cycled or what stage of cycling it is in.
You also need to keep in mind that since you have only two fish left in your fish tank, even if the tank is cycled with the two fish, there is no way you can add several fish into the tank at once and expect the water quality to be perfect. The sudden added bio-load will surely add more ammonia into the system. The amount of good bacteria feed on the ammonia produced by two fish will not be able to take on the ammonia produced by 4, 5, or 6+ fish without going through another mini-cycle.
Your 40 gallon tank is too small for that many cichlids. Even when it is fully cycled with the maximum amount of ammonia your filter system can handle, your 40 gallon aquarium will not be able to handle the full load of 24 cichlids. You will need something like a minimal 90 gallon fully cycled tank for that many fish.
Unless you live in a tropical area, your outdoor pond will not support these tropical fish (cichlids) for long.
You need to return some of the cichlids, or you need a much bigger tank and it must be cycled fishlessly with pure ammonia.
