Choosing The Right Fish For Your Aquarium

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In any aquatic store you can find hundreds of different species alongside each other - but not all these fish can be kept together, and choosing the wrong fish can result in disaster for your aquarium.

Choosing fish from a retailers tanks

Choosing the right fish is not an easy job for anyone new to the hobby, and most experienced aquarists have at some point purchased a species they would not have gone near in hindsight. A few simple steps can help you to make sure the fish you purchase are all compatible and will live out the duration of their lives happily in your aquarium.

Know your water conditions

A basic knowledge of water chemistry is important for many reasons in fish keeping and keeping an eye on ammonia, nitrite, and nitrate levels will help you avoid any serious health problems. Having a rough idea of your aquariums pH and hardness levels will also help you choose the right fish, since not all fish will live in the same conditions, and dramatic changes can kill many delicate species. Knowing what your water parameters are will allow you to match your water conditions to those of your retailer, ensuring that new fish can settle into your tank as quickly as possible.

Keeping lists

A good retailer will know if the fish you wish to purchase will mix with the fish you already have, but if you are not aware of the names of all the fish you have, your retailer can do little to help. Always write down the names of any fish you buy and keep an up to date list of your stock. You can then easily show your retailer your list before you purchase any fish. Should any disasters happen and you find out later on that some of your fish are incompatible, you will at least have a good argument for returning the fish if your retailer previously approved the mix with your list.


Research before you buy

The number one tip, which many fish keepers fail to do, is to research your fish beforehand, and never make an impulse purchase. Browse your local fish shop(s) first and make a note of any species you like, then go away and look them up either in a good book, or with a reliable Internet site. If possible, check more than one source for accuracy. If you absolutely must purchase a fish you have not researched, at least ask your retailer if you can look up the fish in their books, or if you have a good relationship with your shop, ask their advice on the fish. To make sure a fish is suitable for your tank, you need to check its eventual size, character, water condition requirements, and whether it is best in singles, pairs, or groups

Think long-term

Most fish sold in retailers are young specimens, and may change dramatically in size, character, and even colour as they mature. For this reason you need to be aware of what a species will turn into, and whether its fully grown state will be suitable for your aquarium. Never purchase fish that will outgrow your tank on the basis that you 'might' get a bigger tank later on, the chances are the fish will end up outgrowing the tank and being stuck in an unsuitable environment. In the same note, avoid retailers who will offer to take fish back if they grow to big - when you purchase an animal you are responsible for its care for the duration of its life, and in many cases, two years down the line, less reputable retailers will deny offering you a return service. Thinking long-term might also encourage you to purchase fish you might otherwise have not given a second glance. Some fish, such as many rainbowfish species, appear quite dull when young, but mature into very colourful and striking adults. Looking up these fish beforehand will give you a greater choice of fish you may not have considered, and may become your most prized specimens.

Be aware of deformed and abused species

Researching fish you might like at first glance can throw up some interesting facts. Most fish keepers I have spoke to who keep freshwater Parrot Fish were unaware that the fish are a man-made cross of several species and their unusual shape is the result of heavy deformities, including fused bones and miss-shaped organs. If they had known this, they most certainly would have avoided the fish. Whilst the selling of these fish is not illegal, it does encourage the popularity of this type of process, which is detrimental to the fish's welfare, and often causes problems for fish keepers through an increased likelihood of health problems, and unpredictable behaviours. Many fish are bred for different colours and strains, and most are perfectly healthy and acceptable, but deformed species such as Parrot Fish, or Balloon Mollies, should be avoided. A good retailer will never sell these fish, although many stores fall short of acceptable practices and still do. Died fish are less common than in past years, but they do still crop up, so be wary of any fish with very bright or fluorescent colours and if you are in any doubt, try to research the species to find its natural appearance.

Use your retailer

Finally, most fish keepers will be within range of a good store, so do a bit of shopping around to see who is best in your area. Travelling a few extra miles to visit a reputable shop will pay huge dividends in the long run, as they will be able to provide you with invaluable, reliable advice, and good after sales service. The better retailers will also prevent you from purchasing anything unsuitable, as they know it makes good business sense in this trade to turn down a sale on ethical grounds, and keep your custom in the long run.

"Fish will only grow according to the size of your tank"

Some fish, such as goldfish, will reach a much smaller size if they are kept in an environment that is too small, but this is an exception, and even goldfish will outgrow too small an environment. Most fish will continue to grow, perhaps reaching a few inches short of their potential size. Therefore, a fish that naturally grows to 30cm is likely to reach at least 25cm regardless of the size of its environment.

"All community fish live together"

The term 'community fish' only means that the fish will live in a community of compatible species, not that they will all live together. Two community fish, for instance, red-eye tetras and guppies, may not mix since the tetras may nip the fins of the guppies. Choosing only community fish gives you a greater chance of a successful mix, but you still need to check against your current or future stock.

1) Find and use a good retailer for advice
2) Research your chosen species before purchasing
3) Never impulse buy
4) Always check the eventual size of any fish
5) Keep a list of your current stock and any fish you may keep in the future
6) Be aware of the water conditions in your aquarium
7) Remember that fish may look and behave differently as they mature
8) Be aware of, and avoid at all costs, deformed or abused (e.g. dyed) species
9) Make sure you aquarium is a suitable habitat for your potential fish
10) Check you are purchasing the right numbers of any species

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