How To Clean A Fish Tank In 11 Easy Steps

And everything you need to do it 🐟

how to clean a fish tank

As a new fish parent, you love hanging out with your BFF all day, watching him swim around in his new home. But to make sure he’s truly happy (and healthy), it’s super important you keep it clean and tidy.

But if you’re not quite sure how to clean a fish tank, we’ve got you covered.

There are 11 essential steps, according to Jackie Marvel, a veterinary nurse with DodoVet. And we’re here to walk you through them all.

How to clean a fish tank step by step

Here are 11 steps for cleaning your fish tank.

1. Don’t move your fish

You may think that you need to take your fish out of his tank before you clean it, but according to Marvel, that’s not necessarily the best idea.

“You want to clean your fish’s tank with the least amount of stress to them as possible,” Marvel said. “Handling or moving your fish can be a huge cause of stress, so it is OK to leave them in the tank while cleaning since all of the water does not get removed.”

2. Wash your hands

Before you really get into the actual cleaning, prep by washing from your hands and forearms up to your elbows. This is to get rid of any sort of lotion, fragrance or soap on your skin, because those things can hurt your fish.

3. Unplug filters, lights and heaters

“Make sure to do this before water is removed from the tank,” Marvel said. “If [the] water level drops, you don’t want the filter to run dry or the heater to be exposed to air.”

4. Clean the interior glass

This is where your algae pad or scraper comes in. Use it along the inside of your fish’s tank to keep algae from taking over.

(Make sure you’re getting the right one for your tank — always check to see if the pad or scraper is made for glass or acrylic aquariums before you buy.)

Get this algae pad for acrylic tanks from Chewy for $4

Or this algae pad for glass tanks from Chewy for $5

Or try this algae scraper for acrylic tanks from Chewy for $9

Or this algae scraper for glass tanks from Chewy for $9

5. Remove decorations

Take out any plants, rocks or other decorations to make sure you’re getting any debris that’s underneath them. You can also use a toothbrush to spot clean any algae that may be on them.

6. Bust out the gravel siphon

Now’s the time to clean any debris and algae buildup off the gravel in your fish’s tank, with a little help from your gravel siphon.

As you’re doing this, Marvel recommends transferring old water into a bucket that you only use for cleaning your aquarium. You should keep going until the water level in your fish tank has dropped by 20 to 25 percent.

7. Remove and rinse your filter media

For this step, you’ll want to rinse off your filter media in the bucket with your old aquarium water.

“If you wash it with other water, you run the risk of removing beneficial bacteria,” Marvel said.

8. Steer clear of soap

Avoid the urge to scrub your BFF’s tank down with soap and water, because those sudsy bubbles are bad for fish. And any soap particles left inside his tank can also be harmful.

9. Replace the water that’s been removed

But don’t just dump any old water into the tank, because that can be dangerous. You’ll want to test the temperature and quality first.

“Make sure that the water is the same temperature before putting it back in the tank,” Marvel said. “Most bottled ‘spring’ water or well water contains water safe for fish, but it is always best to test your water before starting a new tank.”

10. Add some dechlorinator

This will make sure the water’s safe for your fish.

“Chlorine is toxic to all fish, causing severe gill damage, which leads to death,” Marvel said.

11. Don’t clean the filter just yet

It’s actually better to not clean the tank and the filter at the same time.

“Wait two weeks to clean the filter,” Marvel said. “[It] contains some beneficial bacteria which will replace what was lost when cleaning the tank.”

Why you need to clean your fish tank

The water quality in your fish’s tank is crucial for his health and happiness, which is where cleaning his tank comes in.

“Even if the water looks clean, it could be harmful for your fish,” Marvel told The Dodo. “If the tank is not maintained, harmful ammonia will build up in the tank, which causes severe harm to fish.”

How often should you clean your fish tank?

There’s no universal timeline for cleaning a fish tank, because it depends on many factors, like how many fish you have, how big your tank is, what kind of plants you have in it and what type of aquarium it is.

But there are some things every fish parent can do on a regular basis for a little maintenance and upkeep.

“There are daily, weekly and monthly steps you can take to make cleaning less intense and safe for your fish,” Marvel said.

Daily things you can do for your fish’s tank

According to Marvel, these are things you can do every day to make sure your fish has the best home possible:

  • Evaluate your fish’s behavior — Look for things like swimming upside down or sideways, staying low in the bowl, struggling to swim to the surface or an inability to swim. You should also look for physical abnormalities, like a bloated belly, flaky patches, or red or discolored eyes. (And if you have multiple fish, pay attention to whether or not this is happening to just one fish or all of them.)
  • Evaluate your fish’s appetite — Check to see if your fish isn’t eating, spitting out his food or if there’s a lot of uneaten food at the bottom of his bowl.
  • Remove excess food
  • Monitor water level
  • Check water temperature — According to Marvel, a good water temperature range is between 76 and 82 degrees Fahrenheit. But some species of fish need a different temperature range, so make sure you do your research and chat with your vet to figure out what’s best for your BFF.

Weekly things you can do for your fish’s tank

These are some things you can do for fish tank maintenance once a week:

  • Perform water quality testing
  • Scrub algae from sides of aquarium

Monthly things you can do for your fish’s tank

Here are some things that you should do once a month to keep your fish’s tank in good shape:

  • Rinse bio filter
  • Vacuum gravel
  • Scrub decor

If you have a saltwater fish tank, you’ll probably have to put in a little extra care when it comes to cleaning.

“They require more advanced water testing [and] more frequent cleaning, including the lid of the tank, which can collect salt deposits,” Marvel said.

What you need to keep a fish tank clean

You’ll need some supplies to keep your fish’s tank nice and clean. Here are the necessities, according to Marvel:

And there you have it — how to clean a fish tank and take care of your aquatic BFF straight from an expert! Just follow these steps and your BFF will be so happy to have a spotless home.

Want access to a vet 24/7? With DodoVet, you can connect via video chat, phone or text with an empathetic veterinary expert who can help you be the best pet parent you can be. Say goodbye to Dr. Google and have all your pet parent questions answered anytime, anywhere. Learn more here.

We independently pick all the products we recommend because we love them and think you will too. If you buy a product from a link on our site, we may earn a commission.