How to clean a fish tank

Fish & Reptile Supplies

Some early research into fish has indicated that some fish may be able to recognize familiar human faces. While it’s not conclusive, it’s interesting to know that your fish may recognize who regularly cleans their tank.

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Fish tank cleaning methods

Cleaning your fish tank can be an arduous task. Not only does cleaning your fish tank make it look great, but it also boosts the health, longevity, and even the happiness of your fish. 

When fish tanks are not cleaned, nitrates and metabolites build up, making the tank look bad and affecting the health of the little swimmers inside. Even if you have a filter, most tanks require cleaning at least twice a year.

The best way to clean your fish tank

Prepare your temporary tank 

The first thing you’ll need is to fill a bowl about halfway with some water from your fish tank. This will make sure that you have somewhere to put the fish while you clean because, unfortunately, you can’t leave them in there. What’s more, using the tank water will help the fish not get too shocked by a sudden temperature and PH change, which could be catastrophic. You can use a separate fishbowl or large bowl that you may already have in the pantry.

Net your fish

Next, it’s time to net the fish. Depending on what ornaments or plants you have in your tank, this could be easy or a little challenging. The critical thing to remember is that you don’t want to hurt the fish. This means that you should scoop the fish in the direction they are swimming. Next, quickly take them out and put them into your separate bowl.

Remove the ornaments and plants 

Now it’s time to get cleaning. First, remove all of the plants and ornaments from your tank. Next, thoroughly rinse them in the kitchen sink. Be careful not to use any soap or detergent that could upset the tank’s PH when you put it back in with the fish. You want to make sure that any algae or dirt is thoroughly removed. The rinse clears any nitrates or metabolites from the structures, so it doesn’t mess up your tank once you’ve made it immaculate.

Keep your fish happy

You’ll be adding freshly treated water to your clean tank, but in the meantime, it’s important to get your fish prepared for the change. If you add them straight from the dirty water in their temporary bowl straight back into a tank of freshly treated water, it can be a shock to their systems. 

Prepare some treated water using a water conditioner. A good rule of thumb is using one drop of water conditioner per half a gallon of water, but you should be careful to use the instructions provided on your specific water conditioner. 

Take a cup and remove some of the dirty water from the temporary bowl where the fish are waiting. Replace the same volume of water with the newly treated water. Do this every few minutes while you carry on cleaning your ornaments and the rest of the tank.

Complete the clean 

Now it’s time to prepare some new, clean water for the tank. The water needs to be treated before you add it to the tank using the same ratios and instructions as above.

But first, scrub down the sides of the tank with a solution-free cloth, making sure that any dirt or debris is removed from the tank’s walls. Once that’s finished, you can add your new, treated water into the clean tank. Finally, return the fish to the tank using the net to complete your clean. 

What you need to buy for cleaning a fish tank

Marina Blue Fine Nylon Net with Handle

Marina Blue Fine Nylon Net with Handle

This sturdy net is great for people who need to remove any kind of small fish from their tank. The mesh nylon is perfect for users who want to make sure that their fish is safe and comfortable throughout the tank cleaning process.

Where to buy: Sold by Amazon and Chewy

Koller Products Panaview 1-Gallon Globe Fish Bowl

Koller Products Panaview 1-Gallon Globe Fish Bowl

This bowl is a great option for users who want to store multiple fish in a safe space while conducting their clean. What’s more, the one-gallon jug can easily be stored away after use.

Where to buy: Sold by Amazon 

Tetra AquaSafe Plus Water Conditioner

Tetra AquaSafe Plus Water Conditioner

This water conditioner is great for both freshwater and marine fish to make tap water instantly safe for them. The fast-acting solution also ensures that harmful chlorine, chloramines, ammonia and heavy metals in aquarium water are fully removed from the water.

Where to buy: Sold by Amazon and Chewy 

JOEY'Z 10QT (9.5L) Heavy Duty Sturdy Spout Pail Bucket

JOEY’Z 10QT (9.5L) Heavy Duty Sturdy Spout Pail Bucket

This bucket will work great for any size of tank. The high sides also mean that if you’re using a siphon, it will not creep out and onto your floors during your clean.

Where to buy: Sold by Amazon 

Aqueon Aquarium Siphon Vacuum Gravel Cleaner

Aqueon Aquarium Siphon Vacuum Gravel Cleaner

The siphon will make sure that not only will all the dirty water be out in no time but the gravel will clean too. What’s more, its handheld priming bulb will make the process super quick.

Where to buy: Sold by Amazon and Chewy 


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Lauren Farrell writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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