There are many reasons why cichlids have remained a staple of the aquarium hobby. Their large size, animated behaviour and the relative abundance of a variety of colours, shapes and sizes, has enabled them to remain the largest group of fish available worldwide.
However, cichlids are not without their problems. The aggressive nature of most of the large cichlid species is the most common problem encountered by hobbyists while keeping these species. This article will seek to explore methods which can be employed to reduce aggression and aid in the maintenance of a peaceful cichlid aquarium.
Dither Fish and Target Fish
‘Dither fish’ is a general term, most commonly referring to schooling fish which serve the function of reducing timidness in larger fish species, most commonly cichlids. ‘Target fish’, on the other hand, refers to fish which function as ‘targets’ for large aggressive cichlid species. Target fish are most commonly large schooling fish, typically silver in colour. Examples include; silver sharks, silver dollars, tinfoil barbs, etc. These fish are intended to distract the cichlids from one another and thus limit aggressive fighting between cichlids. The principle of target fish is simple, yet effective. In a closed aquarium environment, the inhabitants of the aquarium have little chance to avoid other fish, unlike in nature, where there is abundant space and opportunity to escape from aggressive individuals. That being said, target fish should be fast enough to avoid being killed by the cichlids. All the before-mentioned species match this specification.
‘Crowding’, is the technique of placing too many fish in a relatively small aquarium. Obviously, this has downsides, such as a heavy bio-load, which can lead to excess nitrate, etc. However, this technique works well with large African cichlids, especially those that form colonies in nature, such as, Cyphotilapia frontosa. Crowding prevents cichlids from forming distinct territories. This is important, as allowing cichlids to establish territories encourages territorial aggression. Having many fish also results in any aggression being divided between many individuals, rather than being focused on a single individual.
Crowding is a method which should be adopted from the beginning, if at all. If you decide to ‘crowd’ in order to prevent aggression, do so from the start. There is no point in putting a small amount of fish in an aquarium and letting them establish territories and then trying to add more fish in an attempt to crowd later on. The new additions will, in all likelihood, be harassed and then killed within a short period of time.
If you decide to add an appropriate number of fish to your aquarium (the recommended amount) and decide not to crowd, then ensure that each fish has enough space to establish their own territory. The down side to doing this is that most large cichlids establish territories of several feet in diameter, resulting in the aquarist having to purchase a massive aquarium in order to accommodate a relatively small number of fish.
Crowding – South American cichlids
The principle of crowding applies in much the same way to South American cichlids. However, most of the time, it is less effective. The reason for this is simple. South American cichlids, as a general rule, do not live in colonies. Most species in nature live in pairs. As a result, most aquarists do not purchase more than two of a single species. This is fine, if these fish will be the only cichlids in the aquarium. However, the problems start when the aquarist wants to add more than one species of cichlid to a given aquarium.
South American cichlids are known for having distinct individual personalities. This makes them fun to observe, however, it also makes it difficult for the aquarist to judge how a particular individual will behave. Many people have kept several species of South American cichlids in an aquarium without problems. Yet others have had the unfortunate experience of purchasing a fish only to have it systematically kill every other fish in the aquarium. This is the fundamental problem with South American cichlids. While there are no set rules for dealing with situations such as the one described above. There is one important aspect to consider which will significantly limit aggression in a South American cichlid community aquarium. That is, breeding…
Breeding Encourages Aggression
The last thing that any aquarist wants in a South American community is breeding. Once South American cichlids start breeding, the aggression goes from zero to maximum power (so to speak) very quickly. A pair of breeding cichlids will force all the other inhabiatnts in the aquarium to one side, while they stay at the other. The aquarium will become a war zone and in most cases, all the other fish in the aquarium will gradually be killed, one by one, until only the breeding pair remains. It goes without saying, that this is the reason why most people prefer to kept only a single individual from each species in a South American community, to completely eliminate the chance of breeding.
There are several ways to limit aggression in large cichlids, with some being more effective than others. When considering purchasing cichlids it is imperative that the hobbyist considers how they will deal with aggression. Keep in mind that size, original habitat in nature and general disposition all play a role.