Essential aquarium care

Essential aquarium care
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While fish might seem like relatively straightforward pets to keep, they do come with the responsibility of ensuring that their habitat remains a clean and hospitable one for them to live in. Aquarium care can be a bit tricky to navigate at first, so here are the essentials that you need to know to ensure your little finned friends remain safe and well.


Check your aquarium’s water

Check your aquarium’s water
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Check your aquarium’s water once a week for its pH, nitrate, nitrite and ammonia levels.

Read up on the chemical tolerances of your particular fish species, so you will know when it’s time for a change of water.

(The people who sold you all the gear may also be able to sell you a water chemical test kit.)

A number of variables affect how often you will need to change the water: how many fish you have, how big they are, the species, the size of the tank, your lighting and the kind of filtration you’re using.

You don’t really change all the water at once.

Just change 10 to 25 per cent of the water in your aquarium, and expect to do it about every two weeks.

Learn more about setting up a fish tank.

To change the water

To change the water
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Round up enough buckets to handle 10 to 25 per cent of the water in your tank.

(You can use the same bucket over and over, but you’ll have to keep stopping the siphon while you empty it out.)

Use a siphon hose to draw the water out. A clear hose is best, so you can see what you’re sucking up.

Don’t refill the aquarium with water straight from the tap. Nearly all tap water has chlorine added, which will hurt your fish. (Many aquarium suppliers will test a sample for you, or you can use a home water-chemical test kit.)

To remove the chlorine, either use a chlorine neutraliser (available from aquarium suppliers), or let the water sit in a basin for 24 hours before pouring it in, giving the chlorine time to dissipate naturally.

Make sure the new water is about the same temperature – within one or two degrees – as the water left in the aquarium.

Not sold on fish? Discover how to find the perfect pet for you.

Nature’s vacuum cleaners

Nature’s vacuum cleaners
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Why not hire some live-in workers for your tank?

The following species are happy to gobble up algae so you won’t have to remove it for them.

Just make sure they’re compatible with the other species in your tank, and check with your local aquarium supplier for species that are appropriate and available in your area.

  • Freshwater

Sucking catfish (Gyrinocheilus aymonieri)

Plecostomus species

Snails (assorted species)

  • Saltwater

Turbo snails


Certain hermit crabs

(check with your supplier)

Removing algae

Removing algae
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To remove algae, use algae scrub pads (available from an aquarium supplier or pet shop) and clean the inside walls of your aquarium whenever the fuzzy little green stuff becomes visible.

If you don’t like having your hands sloshing in water, try a magnetic cleaning system.

One magnet, attached to a scrub pad, goes on the inside of the glass, and another magnet goes on the outside for dragging the scrub pad around.

Remember, algae thrive on light, so the more light your aquarium gets the more algae you’re going to have to clean up.

Prefer a more natural setting for your fish? Learn how to go about planting a pond.

Clean the filter in your tank

Clean the filter in your tank
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Clean the filter in your tank once a week – or more often, depending on the feeding habits of your fish and how many fish you have.

Most tanks have a mechanical filter, and models vary; follow the instructions that come with your tank for removing, cleaning and replacing the filter.

A clean filter means better water, which means healthier fish.

Another filtering tool in your aquarium-cleaning arsenal is carbon.

It gives your water that sparkling-clear look by removing the slightly yellowish cast caused by food and waste.

Carbon may already be a part of your mechanical filter.

If not, you can buy a carbon holder or even make your own.

Put the carbon (available from your aquarium supplier or pet shop) into an old pair of pantihose, tie a tight knot to secure it, then cut away the excess fabric.

Place your carbon filter where it will get good water flow in the tank.

Cleaning an old tank

Cleaning an old tank

To thoroughly clean an old tank – especially if some of your fish were diseased – remove any fish to another container and empty the tank.

Then refill the tank with fresh water and add 2 teaspoons of water cleaner.

Let it sit for at least 30 minutes.

Empty the tank, rinse it well and then refill.

Now neutralise any cleaner residue by using a chlorine neutraliser, following the instructions.

Empty the water once again and rinse.

Now fill your vaquarium with water that you have dechlorinated.

Then your fishy friends can move back in and unpack their bags.

Day to day management

Day to day management
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Here are some preventive measures that can cut down on the time you have to spend cleaning your tank:

  • The location of your aquarium has cleaning ramifications. If you put it in direct sunlight, you’ll have a constant algae battle on your hands, not to mention problems with overheating (the same problems you’ll have if you leave your aquarium lights on too long).
  • The cleaning considerations are not very different for freshwater and saltwater fish. But if you’re a beginner, start with freshwater fish. They’re less sensitive to variations in the chemical levels in the water. Besides, tracking the salinity of a saltwater tank is yet another management issue that could push a beginner over the edge.
  • Don’t give your water beasts too much food. Fish don’t have refrigerators, so leftovers float around, driving up the levels of harmful chemicals. Watch your fish at feeding time. When they begin to slow down their rate of eating, dinner’s over; don’t add more food.
  • Inspect your fish every day to see whether they have any injuries, infections or parasites. When you buy new fish, let them stay in a ‘guest room’ for a month – a separate quarantine tank – so you can monitor them for any diseases that could wipe out the rest of your fish.

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