Choosing Freshwater Tropical Fish

The choosing of the fish for your aquarium should not be rushed.  The success of keeping fishes in captivity depends upon the selection of healthy, suitable stock, followed by proper handling and a careful introduction into the aquarium.

Which Breed of Fish to Buy?

First, decide if you want a species or a community aquarium.  If deciding to go for a community aquarium, choose a variety of fish that will live at different levels of the aquarium, for instance Zebra Danios live at the top, whilst a Tiger Barb will tend to live in the middle.

Work out how many fish you can get in your aquarium, (see here for the calculation), and remember to look at the size the fish will grow to, not the size they are in the shop.  I would recommend starting with fairly hardy fish, and if you are in any doubts, chat to the staff at the aquarium shop.

Remember to buy sufficient of each breed, for instance if purchasing Black Mollies, buy one male for every 2 or 3 females, or if purchasing Glowlight Tetras, because they like to shoal together, buy at least five.

However tempting it is, do not purchase all the new fish for your aquarium at once, purchase one or two varieties and let them settle in for a couple of weeks before buying the next ones.

How To Choose

Only purchase fish from a reputable aquatic supplier where they have knowledgeable staff.  Any reputable dealer will keep newly arrived fish in quarantine for a while before selling them to the public, so check that they do so.  Also inspect the aquariums which the fish are being kept in – are the tanks well looked after, with no dead fish in them?

Look at the fish you want to buy – is it swimming with its dorsal fin erect?  A folded down dorsal fin usually indicates an ailing fish.  The fish’s body should be well-filled, the colours should be bright, and they should swim effortlessly, with no undue wobbling.  Do not purchase any fish with any obvious defects.

Bringing Them Home

The treatment your fish receive at this stage of their life from a dealer’s tank to your aquarium is yet another ordeal for the fish.  A fish that is under stress is more likely to contract a disease, so be as gentle as possible with them.  Generally fish are sold in plastic bags, but if you have a way to go to take them home, you may need to wrap them in something to stop the water cooling too much.

Whatever you do, there will always be a difference in temperature between the aquarium and the plastic bag, so as soon as possible the bags will need to be floated on the top of the aquarium.  After a few minutes the water will be the same, and the fish can be released.  If there are other fish in the aquarium already, I often find that feeding them at the same time will create a diversion, and allow the newcomers to find a place to hide whilst getting acclimatised.

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