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How To Set Up A Tropical Fish Tank

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Tropical aquaria are beautiful, relaxing to watch and fascinating to keep. Here’s some advice for aquarium success.

Buy the largest aquarium that you can afford and will fit your available space. Small aquaria can be kept successfully, but as a general rule, bigger tanks are much easier to look after. Start with at least a 50 litre tank.

Get a good filter

A filter will keep the fish alive and make the aquarium much easier to look after. Ensure you read the instructions so you can install and maintain it properly.

Be patient

Aquaria take time to mature (a process known as ‘cycling’), and a freshwater tank is not mature until at least six weeks after initial set-up. You can begin to stock it with fish from day two, but start with hardy types and build the numbers up gradually. If you stock too heavily in the first couple of weeks, you will overwhelm the filter’s ability to process fish waste, and the fish may get sick or even die. Even when your tank does reach maturity, don’t be tempted to overstock it!

Do regular maintenance

You don’t wait until the engine in the car is rattling before you give it a tune-up, so don’t wait until the aquarium is filthy and smelly before you do some maintenance. Do a partial water change of 20% to 30% at least every two weeks. Service the filter and vacuum the gravel at the same time.

Use a water conditioner

When you add new water to the aquarium always use a water conditioner to remove the chlorine from the tap water. Most water conditioners also add beneficial bacteria and/or plant extracts that are good for the fish as well.

Feed appropriately

Overfeeding is the number one cause of long-term aquarium problems, as leftover food can decompose and pollute the water. Feed the fish two or more times a day, but never give more food than the fish will eat immediately. Make sure any bottom-feeders or herbivores are catered for as well.

Manage the light

Too much light from either the aquarium or the environment will encourage the growth of unsightly algae in an aquarium. The darkest place in the room is usually the best place for an aquarium. If you want to view the fish, only light the tank when you are at home. If you have live plants in the aquarium use a plant-growth tube and keep it on for eight to 10 hours a day.

Educate yourself about fish

You don’t need to be an expert, but at least learn the basics about the fish you plan to keep. Be aware that some fish grow quite large or can become aggressive, and most will eat other fish if they can swallow them. Find a knowledgeable pet store that will give you good advice – it will make keeping tropical fish so much easier.

Finally, ensure you check on your fish every day to identify any issues before they become big problems. It’s also a great excuse to enjoy watching your fish!

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Written by The


Written by The Team

A team of specialists with backgrounds in animal nursing, animal care, and all things pet related.