Decorations are a great way to provide fish with a happy and healthy environment in an aquarium. But they get dirty with time so it’s important to clean them safely. One important aspect of maintenance is cleaning the decorations in the tank. While often people use bleach for cleaning hard surfaces but it can be harmful to fish.

So in this article, we will go through how to clean fish tank decorations without bleach in five easy steps. So whether you are a beginner or an experienced fish keeper these tips will be very useful for you. Read on to learn these new tips and tricks for keeping your tank decorations looking their best.

1.  Gather Materials

It is important to know what materials are required to clean the decorations. It will make your work easier and smooth.

●    Water:

Clean water will be needed to rinse debris and dirt off decorations. I will suggest you use boiled or warm water to clean the decorations. It will kill the bacteria.

●    A Bucket:

A bucket large enough to hold the decorations while they are being cleaned so they won’t get dirty again

●    A Scrub Brush or Toothbrush:

 It will be used to rinse and remove algae. It can easily remove brown algae present on decorations.

●    Mild Detergent:

            A mild detergent such as vinegar can be used to clean decorations. But it is important to completely sock the decorations before adding them to the fish tank.

These materials are needed to clean your fish tank decoration without using any toxic acid or bleach.

2. Remove Decorations from Tank

How to Clean Fish Tank Decorations without Bleach
Removing Fish Tank Decoration from Tank

 Next is to remove all the decorations very carefully from the tank. It is advised to remove decorations very carefully as this process might disturb the fish. One by one remove all the decorations. It’s crucial to handle the decorations delicately when taking them down to prevent any harm. Using a net or carefully removing each ornament from the water may be the simplest way to remove them, depending on their size and nature.

Removing decorations when the tank is not in use will minimize the stress on the fish. Turning off the light when decorations are removed will not stress the fish anymore. Now you can do your cleaning easily without worrying about the fish in the tanks.

3. Clean Decorations with Hot Water

Hot water can be very useful to remove debris from your decoration. Boil water in a tub and put decorations in it to cool down. Hot water will also kill other harmful bacteria on the decorations making the decorations safe for fish in your aquarium. When the decorations are cool down you can remove them from hot water to soak them in the heat. 

Please Note: All decorations cannot withstand hot water so you can use warm tap water for such decorations to avoid any damage to decorations or plastic plants

4. Use a Toothbrush or Aquarium Brush for Algae

A toothbrush or aquarium brush can be very useful to remove algae from hard decorations. Use a brush to scrub the stubborn dirt and algae. Your used toothbrush can do a great job in cleaning.

We recommend using a toothbrush for algae as it can reach places where an aquarium brush is not suitable. After scrubbing the decoration, use hot water to remove the dirt and algae. Let the decorations soak in the heat for 30 minutes.

5. Use of Mild Detergent (Vinegar)

Mild detergent is not harmful to most of the fish in aquariums but if you have koi and goldfish you can skip this step. Vinegar is irritative to sensitive fish like koi and goldfish. But if you don’t have koi and goldfish you are good to go. You can use a mild detergent like vinegar to remove most of the dirt. You can use vinegar to clean aquarium decorations by combining white vinegar and water in equal amounts in a spray bottle and then spritzing the ornaments with the mixture. Soak the decorations for 10-15 minutes, and give them a gentle scrub with a soft-bristled brush.

Properly rinse the decorations with water, before reusing them in the aquarium. As it’s vital to remember that since vinegar may be harmful to some of the living plants and animals, it shouldn’t be used in aquariums with living plants or fish inside the tank.

Frequently Asked Questions (FAQs)

Can I use baking soda to clean fish tank ornaments?

Yes, You can use baking soda to clean fish tank ornaments but it is advised to use it with caution as it is alkaline, and using it in large amounts can be harmful to fish.

How do you clean a fish tank without bleach?

Steps to clean fish tank without bleach:

  1. Gather your cleaning materials
  2. Remove decorations from the tank
  3. Use hot water to clean the fish tank
  4. Use a toothbrush to remove stubborn dirt and algae
  5. Use a mild detergent like vinegar

Can bleach harm fish?

Bleach can be harmful to fish if used more than the desired amount of one teaspoon of bleach per gallon of water. You should closely monitor the ph level of water.


Overall, keeping your fish tank decorations clean and maintained will not only enhance the tank’s beauty but also create a safe and healthy environment for your fish. Stained decorations can be harmful to your fish’s health in a fish tank. By following these five easy steps you can clean your fish tank decorations without using bleach. Now your decorations are as clean as new and are ready to be placed back in the aquarium one at a time.