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How To Clean Algae From Fish Tank Ornaments (8 Simple Steps)

Lindsey Stanton Profile Picture

By Lindsey Stanton

Cryptocoryne Parva Aquarium Plants

That icky green, slimy substance that grows in your aquarium is algae, which nobody wants. Algae growth can be detrimental to the health of your aquarium; plus, it looks awful and smells really bad.

However, algae growth is a normal part of having an aquarium. It is something that every fish owner has to deal with at one point or another. When it comes to removing algae from fish tank ornaments, thankfully, the process is quite simple.

turtle divider AHThe 8 Steps To Clean Algae From Fish Tank Ornaments

aquarium castle
Image By: Krysja, Shutterstock

As long as you follow the steps we have outlined below, you should have no problem getting rid of all of the algae on your fish tank ornaments. The process is relatively simple.

Removing Algae from Fish Tank Ornaments:
  • Step One: Remove all of the rocks and ornaments in your fish tank that have algae growing on them.
  • Step Two: You want to take all of the aquarium ornaments and rocks and scrub them down with a brush under running hot water. Make sure you have a small and stiff brush to get all of the algae.
  • Step Three: Use the brush and ensure you get into all of the crevices and cracks of the ornaments and rocks. You want to remove as much algae from the decorations with the brush and hot water as you can.
  • Step Four: If you cannot simply remove all of the algae by scrubbing it under hot water, you want to fill a large bucket with very hot water. You want to have a bucket big enough so you can completely submerge the ornaments and rocks.
  • Step Five: Mix some good old bleach in with the water. You will want to add quite a bit of bleach, about half a cup, for every gallon of water in the bucket.
  • Step Six: Let all the rocks and decorations soak in this bucket for 15 to 60 minutes. This will help loosen all of the algae and kill off any remaining algae, thus stopping it from growing back.
  • Step Seven: After soaking the ornaments in the bleach water, use the brush and some warm running water to scrub them down again, once again making sure to get into all of the cracks and crevices.
  • Step Eight: Rinse the ornaments and rocks off under running cold water. Make sure to rinse them exceptionally well because you do not want any algae getting into the fish tank. This would have disastrous consequences for all plants and fish in your aquarium.

Stopping Algae From Growing Back

Besides removing all of the algae from the rocks and decorations in your aquarium, there are also some steps that you can follow to ensure that this algae does not come back with a vengeance.

Follow the tips outlined below to prevent algae from growing on your ornaments.

  • Aquarium Lights: Light is a significant source of energy and life for algae. Depending on how much light your fish and plants need, this can be a problem. However, a good way to ensure that algae does not grow back, at least not too quickly, is to leave the aquarium lights off for at least 16 hours per day. Without a good light source, algae has a tough time blooming.
  • Fluorescent Bulbs: If you use VHO or fluorescent light bulbs, you will want to change them every six months at the least. As these kinds of light bulbs get older and degrade, the wavelength of light that they give off changes. These changes in light wavelengths are often a big cause of algae growth.
  • Replace Water: Make sure you replace around 15% to 30% of the water weekly (more on water changes here). This will help remove algae spores and particles from the water. Algae can multiply very quickly, so this is fairly important.
  • Skimmer/Filter: Look over your protein skimmer and your filter at least once per week. An effective and well-functioning filter and protein skimmer can make a big difference in keeping algae at bay. Also, the filter removes fish waste from the water, fish waste which produces ammonia—ammonia which causes algae to grow.
  • Water Tests: You should perform weekly tests on the water in your aquarium for things like ammonia and nitrite. Algae grow really well when there is a lot of ammonia and nitrite in the water. Testing for these substances will help you determine the problem and will help you find the right solution.
  • Tank Cleaning: Cleaning your aquarium on a regular basis will help stop the algae from growing back as well. Removing uneaten food, fish waste, and any other source of contamination is key. Algae feed on various substances, so having a clean tank is a great way to stop it from growing.
  • Remove Dead: Always make sure to remove any dead fish, plants, or other dead creatures from the water. They give off ammonia, which algae love feeding on.

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Cleaning algae off decorations is not very hard, but ensuring it does not grow in the first place can be tricky. It doesn’t take long for the algae to take over! Maintaining a clean tank is crucial for the health of your marine life and their environment. However, if you follow the steps and tips outlined above, you should be able to deal with algae growth with no problem.

Feature Image Credit: Greenpro, Amazon

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