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Back To Fish
Why is my fish sick?

Why is my fish sick?

Fish are fascinating pets, but they're reliant on you for their care and environmental health - so it's important that you maintain a healthy place for them to live. By staying on top of the following checklist, your pet fish should enjoy a long, healthy & happy life.

Water quality

One of the main reasons behind most family fish deaths is poor quality water – after all, they not only swim in it, but source their oxygen from it. It’s important that the pH, ammonia, nitrite and nitrate levels are always at a healthy level. If that sounds like a lot of work, then an API Master test kit is a quick way to regularly measure all levels. Alternatively, head to your local Animates with a sample of your fish’s tank water for a free water test.

Note: An inexperienced fish owner may not realise they have to prepare their new aquarium’s filter to handle fish waste through a process called ‘cycling.’ An ineffective filtering system and lack of good bacteria in your tank creates elevated levels of ammonia, which can harm the fish and result in cloudy water. So when you first set up your aquarium, be sure to condition and cycle the water right away. Give it time to get the conditions right, before you add fish. For more information about the Nitrogen Cycle and cycling your tank click here.

Keep the aquarium in good condition

Investing in a high-quality filter is essential to the health of your fish. A high-quality and quiet water filter will keep your tank cleaner for longer, while investing in an air pump will keep the water aerated so your fish won’t suffocate from a lack of oxygen. And if one of your fish looks a little sick, try using an aquarium treatment that safely treats all bacterial and fungal infections.

Regularly change tank water

Good fish care requires changing 25 per cent of aquarium water every week. While you’re siphoning the water off, use a gravel vacuum to remove fish faeces. When you replenish the water later, be sure to add water conditioner.As part of your tank maintenance routine, it's important to regularly check your heater is maintaining the temperature of your aquarium appropriately. Make sure the water temperature hasn’t dropped below ideal conditions for your fish (ideal temperature varies between fish species).

Give your fish a balanced diet

Fish are opportunistic feeders and require a varied diet to get the nutrition they need, including digestible protein, vegetable matter and carbohydrates. Speak to your local Animates expert to find out what foods, across our range of flakes, pellets and frozen foods are best for your fish. Overfed fish can become unwell, so provide only as much food as they can eat within two minutes, two to three times a day.

Introduce your fish carefully

If your fish died immediately after being put into its new home, then it’s possible they weren’t introduced to the new habitat correctly. Fish are sensitive animals, so check our pet care article on how to introduce new fish to your tank for more tips.

Sickness in an aquarium is not uncommon but predominantly occurs when water conditions are poor, or in times of stress or changes for the aquarium. To learn more about fish health and preventing the spread of illness, check out our Fish Health 101 article.

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