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Solving common fish tank problems

Owning fish and displaying them in a beautiful tank is an enjoyable hobby, but solving common fish tank problems takes dedication and hard work to keep your fish healthy and your tank pristine.

A dirty, damaged tank can harm your fish and won’t impress anyone, so you need to stay on top of any fish tank problems that you might encounter.

For beginners who are looking to keep their tanks clean and functioning effectively, here’s a list of the most common fish tank problems you might encounter and how you can solve them. 

Fish Keep Dying

If your fish never last long in your fish tank, then you need to find the cause quickly so that you can any new fish you buy will live long, happy and fulfilled lives. 

Some common reasons for a high fish mortality rate include: 

• Buying the wrong type of tank: If your tank doesn’t support the species of fish that you’re introducing, then they won’t last long. Check out our guide to the best beginner fish tanks of 2021 to find out more about which tanks suit which fish and find a new tank for your home.

• Not keeping your tank clean: If your tank is dirty and full of old fish food and grime, then your fish will die quickly. Learn how to clean your fish tank and introduce plants that will help you to keep it cleaner for longer. 

• Crowding: If you introduce too many fish into your tank, or be unfortunate to have a snail infestation (from your fish food or plants) -  then they won’t have enough space in the tank and will become ill and die. Learn about the aquarium space you need for the species you are looking to introduce into your tank so that you can give them enough space to live happily. 

• Dangerous decorations: If you’ve chosen to decorate your tank with cute castles and rocks, then check that they are safe and aren’t too sharp. If you notice that many fish are dying near to these decorations, then remove them to see if they are the problem. 

Algae Build Up

Algae will occur in every fish tank, but too much of it can make the water appear dirty and potentially harm your fish. As such, you need to make sure that you clean it out regularly and that it doesn’t grow too quickly.

If you notice that algae are rapidly growing in your tank, then it could be for a range of reasons. These include:

• Food build-up: If you feed your fish too much, and they don’t eat it all, then this could cause algae growth your tank. Try reducing your fish’s diet and making sure that you scoop out any uneaten food with a net at least once a day.

• Position of your aquarium: Fish tanks that are in direct sunlight can grow more algae than others because algae thrive on natural light. Try moving your tank so that it is a slightly shadier position to reduce the growth of algae. 

• You leave your UV lights on too long: UV lights are prevalent in marine fish tank set-ups, but they can also help algae to grow and flourish. Turn off your lights during the day, and only turn them on when you want to impress or enjoy your fish tank to the fullest. 

You don’t change your water frequently enough: Water quality is crucial for the health of your fish, especially in tropical and marine fish tanks, as the fish in these tanks are particularly sensitive to their environments.

When cleaning your tank, you should try to change as much of the water as possible, while leaving a small amount for the fish to acclimatise to slowly. Clean your tank regularly, at least once a week, so that it remains clean and functions properly.

Cloudy Water

Cloudy fish tank water doesn’t look very nice, and it can also harm your fish if left unattended. As such, as soon as you notice that your tank water is becoming cloudy, you should try to remedy the problem.

Easy ways to deal with cloudy fish tank water include:

• Clean your tank more often: Cloudy fish tank water could be the result of a dirty tank and a build-up of leftover fish food, detritus and bacteria. Clean your tank more often and change at least half the water to keep it fresh. 

• Add a filter and keep it clean: If you haven’t already got a fish tank filter, then find one that will suit your tank and then make sure that you keep it clean. Keeping your filter clean will allow it to pull dirt and grime out of the water efficiently. 

• Remove uneaten fish food: Again, old fish food is a common cause of cloudy tank water, so make sure that you remove any uneaten food and try reducing the amount you feed to your fish to keep the water clear. 

If you have more serious problems or need expert advice, then feel free to reach out to me here or speak to your fish tank provider. 

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