Creating a Fish Community

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One of the great attractions to fish keeping is the variety of different types of fish available. The differences in size, behaviour and environmental needs however, mean that many of these fish are not compatible.

Ruby Rainbow Shark

Choosing a suitable mix of fish may not always be a simple case of 'good fish, bad fish' - some livebearers may need to be kept in single sex groups or with more females than males, other fish will exhibit different behaviors depending on which fish they share an aquarium with. To create a 'community' aquarium, it is important to understand the different needs and behaviors of fishes. A 'community aquarium' is a term that is used rather loosely and can be applied to different situations. Many fish are often described as 'community fish'; these are normally species that are small and peaceful. A 'community fish' however, may not do well in a 'cichlid community'. Another way of looking at the subject is that two 'community fish' such as mollies and rummy-nose tetras should live quite happily together, except they require completely different water conditions. Creating a good community of fishes in the aquarium depends not just on whether the fish are peaceful, but on their environmental requirements, size, and how they interact with other fish species.

General community

The most common type of aquarium is a general community; a mix of fishes which are peaceful and will live in a broad spectrum of water conditions. To create a good general community a mix of shoaling, surface dwelling, scavenging and algae-eating fishes can be used. The aquarium should contain a few live plants and hiding spots under wood and/or rocks.

Softwater community

Many popular and colourful aquarium fish prefer to be kept in soft water, similar to the conditions found in their natural habitats. Colourful tetras such as cardinals, rummy-noses, and black phantoms will only show their best colours in a softwater aquarium. Other fish such as the South American dwarf cichlids also prefer soft water; these fish include the beautiful ram and the Apistogramma group. A softwater community may include many fish that are peaceful yet exhibit territorial behavior and unusual personalities.

Hardwater community

Livebearers such as guppies, platies, and mollies are in fact hardwater fishes, despite the fact they are often recommended for any community aquarium. Other hardwater community fish include rainbowfish and some barbs. Quite a few of these fish also benefit from a little aquarium salt in the water, although this has more to do with disease prevention in heavily bred species than in recreating natural water conditions.

Planted community

A 'true' planted aquarium will have a dense mass of plants covering almost every area of substrate available. In the process of caring for the plants, and through processes carried out by the plants themselves, the aquarium conditions often include low oxygen levels and fluctuating pH conditions. Fish suited to a planted community must therefore be able to cope with such an environment. The majority of tropical aquarium fish will benefit a great deal from a heavily planted tank, if only through the sense of safety it provides for the fish. In fact, many small and timid species will only do well in a heavily planted tank.
Air breathing fish such as gouramies and corydoras are ideal for planted tanks, as are many small fish such as tetras. 'Useful' fish species such as algae eating and scavenging shrimps and fish are also ideal for a planted community.

Central American cichlid community

The cichlids of Central America are often large, aggressive and territorial. Creating a community of these fishes is difficult at best, but not impossible. The key is to carefully select your final mix of fish, ideally after seeking further knowledge through reading or advice. Choose a mix of fish that all reach a similar size and introduce them all when they are young. Avoid having two males of any one species, although there are some exceptions where this is allowed. The aquarium should be well filtered to cope with the waste produced by these fish, which are all messy feeders. A large aquarium is a must, as well as large decor that is either fixed or unlikely to topple. Once these fish get big, they often have a tendency to move any decor they can. Only a few select species of plant are tough enough to withstand the attentions of these fish, so choose carefully.

African rift lake cichlid community

Many people are attracted to the rift lake cichlids; they are bright, colorful and active fish. They are also highly aggressive, territorial and almost impossible to mix with non-rift lake fishes. Providing these fish are kept in a heavily stocked aquarium, with a mass of hiding spots amongst rockwork their aggression can be brought under control. Ideally, stick to fish that originate from the same lake (i.e. a Malawi community or Tanganyikan community) and again, purchase all the fish when small. These fishes are also hardwater fish and will benefit from calcareous rocks or substrate, such as those designed for marine aquariums. In some cases, a few carefully chosen catfish can be kept in a rift lake community.

Biotope community

The reason so many people keep fish is the fascination of creating a whole living environment in a small area where fish can be observed carrying out their daily activities as they would in nature. For many fishkeepers, the best way to enjoy the hobby further is to create a true biotope aquarium. A biotope community should include only fishes from the same area of the world. The idea can be taken as far as possible, including only fishes from specific areas within rivers and only the plants found in that area. The decor should also represent or mimic the natural environment as accurately as possible. Whether it is a Chinese stream bed, Amazonian tributary, European lake or mangrove swamp, a biotope aquarium requires a good deal of prior research and planning. Investigating and understanding about the fish and their environment is however, half the enjoyment of the hobby. A biotope community aquarium is, in most cases, well worth the effort.

Getting the mix right

With all the different types of fish and different communities, it seems an impossible task to select a mix that will all be compatible. The best way to find fish you like is to simply browse the stock in your local shops, or download the thumbnail PDF's from the Think Fish Community Creator or Fish Profile sections and make a note of the species that catch your eye. From that list you can create a community based on the suggestions of your retailer. Check this list with the Think Fish Community Creator, and you can be assured that your chosen mix of fish will all get along.

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