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Choosing tropical fish for your aquarium is a very important part of fish keeping and it’s always a good idea to do your homework on the types of fish that you would like to keep. Some of the key things to research are compatibility with other species which you already have or intend to keep in the future, adult size of the fish, diet, and the fish’s ideal water parameters and temperature.

When purchasing the fish, take time to examine the ones you intend to buy and make sure that the fish you select are in tip top condition. In general shops specializing in the sale of tropical fish and aquarium supplies provide healthier fish. Avoid buying unhealthy looking fish, they may not last long and could infect the rest of the fish in your aquarium. The exception to this being rare or hard to find species which you intend to quarantine for a few weeks and nurse back to full health before introducing to your fish tank.

What to research before buying aquarium fish:

Compatibility of the Fish

Freshwater tropical fish fall into different compatibility groups based on their ability to get along with other fish species.

Community fish are generally friendly toward species of the same size or smaller, but not all community fish are universally compatible with one another.

Semi aggressive fish are friendly toward fish of the same species but can be aggressive toward certain other species, especially over territory.

Aggressive fish are compatible only with larger fish or fish of the same species; otherwise, they can create territory issues and cause harm to one another.

Dietary Needs

It is important to recognize that no one tropical fish food will satisfy the needs of all different types of fish. Each species of fish has their own needs and all tropical fish need variety in their diet. You should vary what you are feeding and give your fish a range of different food types to keep them healthy.

Adult Size of the Fish

One of the most common, and frustrating, myths about fish keeping is that fish will only grow to fit the size of their tank. This misinformation is propagated by the fact that most fish will die prematurely due to inadequate living conditions before they noticeably outgrow the tank they are housed in.

The adult size of a fish is determined by genetics, not by aquarium size.

Tips for selecting healthy aquarium fish:

Check the body of the fish for lumps or white spots.

White spot disease is one of the more common tropical fish diseases. Look out for pin-sized white spots raised away from the body of the fish. Avoid buying any fish from that tank.

Look for complete fins and tail.

Damaged fins might be a sign of disease, or they could be a symptom of fighting between the fish in the same tank. It’s safer to avoid any damaged fish, especially as you might be looking at fin rot and not realise it.

Avoid fish with missing scales.

Similar to damaged fins. A few missing scales aren’t fatal, but it’s better to avoid damaged fish to ensure that you’re not buying a diseased fish.

If you are stocking a new tank, it is probably best to start with a few small and inexpensive fish first.

Just remember to do your research, take your time selecting healthy and compatible fish, and you will enjoy this hobby for years to come.

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