How to clean a fish tank for beginners

If you’re a new fish tank owner, cleaning the tank may seem like a daunting task, but with a few simple accessories you can easily keep your aquarium in tip top shape. If you’re wondering how to clean a fish tank without removing the fish, or without performing a complete water change, carry on reading our guide which highlights how to clean each element of your aquarium with ease.

To make the job even easier, our guide is laid out, step-by-step, in the order you should follow when cleaning your fish tank. We've also included some useful product recommendations so that you can easily get a pro-level clean for a visually stunning aquarium.

Cleaning the aquarium glass 

Before we get started, make sure that you unplug all of your equipment including your filter and any heaters, as they’re not designed to run without water and this could cause damage to the equipment. Additionally, you should make sure you’ve washed your hands and arms up to your elbows. This is to keep any bad bacteria out of the tank when completing just a part water change. 

Cleaning the aquarium glass first to remove any algae overgrowth will make the job easier, as you’ll be able to dislodge the algae and vacuum up the debris when it comes to cleaning the substrate layer later on. 

To clean the glass, or acrylic, you’ll need a specific fish tank glass cleaner such as a non-abrasive algae cleaning pad, and a scraper. General household cleaning wares aren’t appropriate for fish tanks as they can leave residual chemicals in the tank which can harm your fish, and they can leave scratches on your tank. We recommend using the Algae Scraper Pad Deluxe to cover the larger surface areas of the tank, and using the Fluval Razor 2-in-1 Magnet cleaner to remove any stubborn algae and to clean any corners or hard to reach areas. The Tunze Floating Magnet Cleaners are ideal for daily maintenance of algae on the glass, as they are designed to suit several glass thicknesses, and the plastic blades are suitable for acrylic tanks. Additionally, the ergonomic design prevents sand or gravel getting stuck between the magnets to reduce the chance of scratches occurring during cleaning.

Algae Scraper Pad Deluxe & Fluval Razor 2-in-1 Magnets 

You don’t need to remove your fish during cleaning, chasing them around to catch them may actually cause them to be more stressed. Gently clean around your fish to remove excess algae.

How to clean fish tank ornaments, decorations, & plants

It is best to remove any fish tank ornaments and fake plants to ensure thorough cleaning, and leave them out of the tank until cleaning is completed. This will stop any debris settling on them when it is time to clean the substrate layer. Remove each decoration and clean using only hot water and a designated toothbrush or scraper to scrub off the algae. There are also solutions specifically designed for cleaning plastic plants and ornaments to restore their visual appeal. The Interpet Ornament Cleaner is an excellent choice. Alternatively if you don’t have any cleaner to hand and if the algae is extremely stubborn, you can leave the decorations to soak in a hot water and 10% bleach solution. Leave them to soak for no more than 10 minutes, and rinse thoroughly under running water before leaving to dry completely to eliminate any residual chlorine. To ensure optimal safety, you can also use a dechlorinator. After you’ve rinsed the product, leave it to soak in a dechlorinating solution for 15 minutes.

Interpet Ornament Cleaner & Fluval AquaPlus Dechlorinator

If you have chosen to have live plants in your aquarium, they may also need to be cleaned. You should leave them in the tank and gently rub off any debris or algae, so as not to disturb them or cause damage. However, if this doesn’t work you can cut off the old and infested leaves without removing them from the tank. It is not advised to remove your plants because this will mix the substrate, disturbing the balance and stability of the ecosystem in the aquarium. In turn, this can lead to a release of excess organic compounds and ammonia which will cause harm to your tank. 

It is also important to note that using a bleach solution is only recommended in extreme cases of algal overgrowth, and you should never use soaps or detergents when cleaning your plants and ornaments, as it can be hard to remove chemical residue which can be lethal to your fish.

Cleaning aquarium sand and gravel 

Now that you’ve removed all of your decorations, filters, and heating systems, any debris should have settled at the substrate layer and you should have a clear view of your fish. You can leave the fish in the tank whilst you clean the gravel, but you need to ensure that you don’t remove more than 50% of the water at a time. Don’t worry, this step is not as difficult as it may sound, as long as you’re using a fish tank gravel cleaner. 

We would recommend using the Fluval ProVac gravel cleaner to easily get a thorough clean. Despite its name, the gravel cleaner can also be used to clean aquarium sand, though it is a little trickier due to its fineness. Gravel cleaners pick up the gravel and sand through a wide pipe and tumble it to dislodge dirt and debris which is then sucked up through a thin tube, allowing the cleaned gravel to be deposited back into the tank. With sand, you may need to hover slightly above the sand to allow it to be picked up and cleaned without it being filtered out into the waste water bucket. Just in case too much does get filtered out, make sure you have some back up sand to replenish the substrate layer.

Of course, you should also be mindful of small fish, most fish will swim away from the gravel cleaner, but you should pay extra attention to make sure that they don’t get caught in the mechanism! Keep the wastewater in a dedicated bucket, as you can use it to clean your filter media.

Fluval ProVac Fish Tank Gravel Cleaner

Should I clean the filter media? 

One of the trickiest parts of cleaning your fish tank is ensuring the good bacteria colonies aren’t eliminated, as your fish tank will need these colonies to thrive. Beginner fish tank owners are often misled by natural tendencies to make sure every component has been thoroughly cleaned, thinking that this will be most beneficial to aquatic health. However, this simply isn’t the case. Excessive cleaning of the glass, gravel, and ornaments can lead to complete elimination of the bacteria needed to keep a healthy ecosystem within your tank.

A filter is a good way to keep good bacteria present as it houses a lot of these beneficial bacterial colonies whilst also filtering out harmful waste, and therefore it shouldn’t be replaced when cleaning. Changing a filter when cleaning can cause ammonia to spike as there isn’t enough bacteria to eliminate this toxicity.

Some fish tank owners actually prefer to clean the filter two weeks after cleaning the rest of the tank. Although if you have a lot of algae overgrowth you may wish to undertake a small amount of filter cleaning during the cleaning process. In most cases, filter media can be cleaned and  reused for about 3-6 months before needing to be replaced, you will need to clean it at least once per month, but preferably it should be done fortnightly.

To clean your filter media, remove it and gently squeeze the excess water out, and you can also swish it around in the wastewater you previously collected when cleaning the gravel. You can use a small brush to clean the filter housing and elements, removing algal growth. This way you can reintroduce the good bacteria to your tank, whilst still ensuring a good standard of cleanliness.

Replace the aquarium water

Now it is time to replace the depleted water in the tank. You will need a dedicated bucket or jug for this, one that hasn’t been used to house any other chemicals or cleaning equipment. Your water will need treating before placing it into the tank, and the treatment solution will depend on the type of fish you have. Firstly, you should make sure that the temperature is correct, and closely matches the temperature of the tank.

Secondly, you’ll need some dechlorinator or water conditioner such as Seachem Prime as this is essential for removing toxins and heavy metals found in tap water. Place it into the bucket and allow it to rest for a few minutes before introducing it to the tank. You may also need to use other water cleaners, bacteria cultures, or additives, depending on the type of fish you have, so be sure to check the needs of your fish according to their type (tropical, freshwater, etc). Bacteria boosters such as Fluval Cycle add nitrifying bacteria to the filtration system instantly, allowing this essential bacteria to grow within days rather than weeks. Whilst you’re waiting for the water to be primed, you can start to place your decorations back into the tank, but they may need readjusting once you add the new water.

Aquasafe Dechlorinator  & Fluval Cycle

Turn on filtration and heating systems

It’s now time to add your filtration, heating systems, and other systems back into the tank and turn them on. Make sure you’ve cleaned tubes, lights, and anywhere else where algae might grow, this will help to stop any clogs and sludge from forming within the mechanisms. Your tank may be looking a little bit cloudy at this point even after all that cleaning, but the filter will soon take care of this particulate clouding after an hour or so. 

Finally, you’re almost done. You can now clean the exterior of the glass to remove any marks, smudges, and dust. Simply use a damp microfiber cloth to get rid of any marks, there’s no special fish tank glass cleaner required. Although we would recommend avoiding any standard household glass cleaners, if you have very stubborn stains you could use a vinegar solution to help clean the exterior. 

Maintain a healthy fish tank with Aquacadabra

Keeping a perfectly balanced and thriving ecosystem goes beyond supplying food to its inhabitants and cleaning the tank. You can ensure that your aquatic residents have everything they need to thrive with a range of supplies available at Aquacadabra, including water testing kits, treatments, and cleaning accessories.

Each type of tank will be different, and owning an aquarium is always a learning curve, especially for inexperienced fish owners. If you’re unsure of what you need or would like a little more guidance, we welcome customers to contact us for advice on keeping your fish healthy.