How to deep clean a fish tank

How to deep clean a fish tank

Just like any other pets, fish require dedicated care and maintenance in order to provide them with a happy home life, and a clean tank is a critical part of caring for your aquatic friends. While there are ways to keep your fish tank clean naturally by introducing algae-eating fish to your aquarium, manual cleaning should still be undertaken to ensure your fish have a safe place to call home.

In this blog, we’re going to give you an easy step-by-step guide to follow on how to clean each part of your fish tank, from the inside of your tank's filter right down to the gravel or sand substrate so you can ensure you’re giving your fish friends the best home possible.

1. Clean the inside of the glass

If you’re new to maintaining and cleaning fish tanks, you may be surprised to learn that you don’t need to take your fish and water out of the tank in order to clean inside. It’s perfectly safe to clean your tank with your fish still in there so long as you move slowly and carefully.

We recommend replacing your fish tank water by 25% - 40% each week, which you can do while you clean and your fish will still have plenty of space to swim around the bottom while you clean the inside of the glass.

Cleaning the inside glass of your tank is pretty straightforward, however, it’s best done by using certain tools. Having the most suitable equipment to not only help make the job easier, but also to ensure the safety of your aquatic life while leaving a streak-free finish on your tank. Here are a few tools we would recommend for cleaning the inside glass of your fish tank.

1. Cleaning cloth - For wiping off any marks or streaks for a pristine finish, these cloths won’t leave any residue to keep the glass of your aquarium sparkling. You can use these cloths for cleaning the inside of a tank when it's dry or cleaning the outside, but they shouldn't be used to clean a tank with fish and water still inside.

Innotec Aquatec 500 Cleaning Cloth

Innotec Aquatec 500 Cleaning Cloth, from £15.99

2. Glass scraper - These are best for when you come across a stubborn patch of algae or grime on your tank glass. The scraper won’t scratch your glass but acts as a stronger solution when a cloth just isn’t cutting it.

Tunze Magnet Scraper Pico

Tunze Magnet Scraper Pico, from £13.95

3. Algae cleaning mitt - for wiping away unwanted algae growth. The mitt provides a strong grip for when you need to scrub at hard-to-reach areas such as corners.

Python Algae Cleaning Mitt

Python Algae Cleaning Mitt, from £8.99

We would also recommend you use long waterproof gloves to keep your hands warm and dry during this cleaning process. More than anything else, however, It’s important you avoid store-bought cleaning supplies for this cleaning process. This is because, while all of the above products are made for aquariums with your fish in mind, products such as store-bought clothes and wipes may contain bacteria and residue which could harm or even kill your fish.

Using specific aquatic cleaning products will ensure your fish are free from risk during this process.

2. Cleaning fish tank decorations

Whether you have coral ornaments, plastic plants, large rocks or decorative volcanoes, we would recommend you clean these every few weeks to keep them in top condition. While you might find a little algae growth makes for a nice aesthetic on your decorations, too much algae will promote an unhealthy environment for your aquatic friends, so keeping on top of a strict cleaning regimen is a must.

The best way to clean your fish tank decorations is to remove them from the tank completely and submerge them into a bucket of warm water. Give them a good scrub using an algae scraper rather than a regular brush, as these come with retractable blades to effectively get rid of algae without damaging your tank's decorations.

Seachem Algae Scrapers

Seachem Algae Scrapers, from £16.99

Be aware not to use soap, even if you’re finding the algae isn’t coming off, as this can be harmful for your fish when you put your decorations back into the aquarium, no matter how well you rinse them. If you find the algae isn’t coming off then instead prepare a 5% bleach, 95% water solution. Then soak your decorations in it for 10-15 minutes, and this should help take off any excess algae. Before introducing your cleaned decorations, make sure that all of the bleach solution has been removed from the surface.

3. Trim your tank plants

The next step in cleaning your tank is to trim any live plants that you may have in your aquarium. With the water levels low and your tank decorations out of the way, you’ll have plenty of room to give your live plants the care they need.

In order to trim your plants, you’ll need a clean pair of scissors (that are preferably only used for your tank) in order to prune them. If you have floating plants remove about half of them so that you can be sure that your fish are getting enough light and oxygen. As nice as it is to see your live plants thriving, you may compromise the comfort and safety of your fish if you have too many obstructing much-needed oxygen and light sources.

4. How to clean stone, gravel and sand

Now that your glass has been cleaned, your decorations have been removed and your plants have had a nice trim, you will have plenty of space to clean the sand, stones and gravel at the bottom of your tank.

The best way to approach cleaning the rocks, gravel and sand in your tank is to use a gravel vacuum. These amazing tools will remove loose debris from the bottom of your tank. We recommend vacuuming 25-50% of your gravel weekly, but this step should at the very least be part of your deeper cleaning routine as you will need to get under your decorations while you do this as well.

Fluval Gravel Vac - Small/Medium 11080

Fluval Gravel Vac - Small/Medium 11080, from £15.35

5. Clean your aquarium water

Water changes are a very important part of your tank cleaning regimen as doing this will remove waste and dirt, as well as dilute the build-up of toxic elements and increase oxygen levels in the water - all things that will dramatically affect your fish's quality of life.

We recommend changing 25-40% of your water each week. This is best done using a siphon hose to transfer the water from inside your tank into a bucket. You will then need to replace the water you removed with fresh, treated water that is at the same temperature as the rest of the water in your aquarium. To ensure the water is safe for your fish you will want some water quality test kits and some dechlorination solutions to ensure the water is completely balanced before adding your fish.

You will also need a thermometer to ensure that the water you’re adding to the tank is the same temperature as the water already in your tank. If the water temperature is too cold or too hot for your fish it may send them into shock and can be fatal.

Python No Spill Aquarium Siphon

Python No Spill Aquarium Siphon, from £64.99

NT Labs Test Kits - Ammonia, Hardness, Nitrate/Nitrite & pH

NT Labs Test Kits - Ammonia, Hardness, Nitrate/Nitrite & pH, from £8.70

Superfish Aquarium Thermometer

Superfish Aquarium Thermometer, from £3.65

6. How to clean your tank filters

Cleaning your tank filters should be done once per month and we would recommend that you alternate your cleaning routine between your tank and your filter. This is because when you give your tank a thorough cleaning, you will disturb the beneficial bacterial colonies that you need to eliminate the toxins. Your filter will contain these beneficial bacterial colonies already, so leaving your filter as it is for a week or two after your cleaning can help to keep your ecosystem stable and avoid triggering an ammonia spike.

When it comes to cleaning your filter, take your filters out of the tank and remove the filter sponges from inside. Clean these sponges in warm water that has been treated to remove the harsh chemicals and keep them safe for your fish when putting the filter back. Squeeze the sponges under the water to remove trapped dirt and waste. If the sponge is particularly clogged, then it may take a few different washes to ensure it’s been properly cleaned.

7. Cleaning the outside of your aquarium

Once you’ve finished with the previous steps, you can now put all of your decoration and filters back into the tank as you’ve successfully finished cleaning the inside. We can now move on to the outside of the tank! Cleaning the outside is as simple as giving it a wipe and cleaning any dust off of the aquarium lid, stands and lights for a pristine finish.

Once this is done, you can sit back and enjoy your freshly cleaned tank and happy fish!

Commonly asked questions for cleaning a tank

Deep cleaning a tank, especially when it’s your first time, can feel intimidating. So we’ve included a list of the most commonly asked questions when it comes to deep cleaning your fish tank to help provide some answers so you can clean your tank safely and with confidence.

How often should you clean your tank?

The answer to this question depends on a number of factors including how effective your pumps and filters are, the quality of your water, the size of your tank, what types of fish live in your tank and how many there are. It’s important you research what your fish needs and no two species of fish are the same!

However, we know there’s nothing more frustrating than a vague answer. A general rule of thumb for most aquatics is to clean your tank at least every two weeks. You can usually tell when your tank is getting too dirty through the amount of algae that is growing as well, so you can adjust how often you clean your aquarium around this.

Do you remove fish when cleaning your tank?

You do not have to remove your fish while cleaning the tank. As long as you’re careful and do it slowly, you can complete the whole cleaning process without having to move your fish to a different tank.

What to avoid when cleaning your tank.

There are certain things that you should avoid doing or using when cleaning your fish tank, there are certain products that may contain chemicals that are harmful to your fish. To help ensure you’re protecting the safety of your fish - here are a few things to avoid when you’re deep cleaning your tank.

  • Avoid store-bought cleaning supplies including cloths and sponges.
  • Avoid using harsh chemicals such as soap, dishwashing liquid and bleach as these can be fatal to livestock.
  • Avoid using untreated tap water to clean your tank.
  • Do not use extremely cold or extremely hot water in your tank.

Keep your aquarium clean with Aquacadabra

We understand that a lot of effort and time goes into the care and safety of your aquatic friends. We all want to give them a good home and here at Aquacadabra we provide everything from essential water quality kits to aquarium maintenance products so you can give your aquatic friends a safe and comfortable environment.

If you find you need some extra advice and help when it comes to the care of your fish, then you can also contact our friendly experts for more personalised guidance on the maintenance of your aquarium.