top of page

How Do I Clean My Aquarium? Part 3: Cleaning the Glass or Acrylic Panes


Aquarium glass scraper underwater among green and red plants, with Boodleshire Aquatics logo at bottom right.

The ultimate goal when cleaning the glass or acrylic panes of your aquarium is to remove all the algae and buildup while preventing scratches and damage to the silicone. The best way to do this is by properly using the right tools.


Scratches can easily occur from blades, rough sponges, or gravel getting stuck in between a cleaning tool and the pane. The tendency of a substance to be scratched is related to its hardness.


The Mohs scale of hardness is a universal scale of mineral hardness by which substances are rated by the mineral they can be scratched by. Acrylic aquariums are made of cell-cast acrylic and have a hardness of 3 out of 10 on the Mohs scale. Glass aquariums are made of high or low-iron silica glass and have a hardness of 6 to 7 out of 10.


Cell-cast acrylic is manufactured pane by pane when unreacted acrylic is poured between two sheets of glass separated by a gasket to determine thickness of the acrylic pane. This method results in 92% clarity and great resistance to water erosion.


Glass panels or panes are either regular silica glass or low-iron silica glass. Low-iron glass has around 90-92% transparency compared to around 83% of regular silica glass. This is due to 0.01% ferric oxide in low-iron glass compared to 0.1% in regular glass panels.


Low-iron glass is not harder or softer than regular glass, it is only more transparent. With less of the green hue from the lower iron content, thicker panes of low-iron glass on larger aquariums allow for a much higher quality viewing experience of the contents of your tank.


Tools for Cleaning Aquarium Glass or Acrylic

At a 3 out of 10 on the Mohs scale of hardness, acrylic scratches much easier than glass at 7 out of 10. If you opted for acrylic over glass due to its lighter weight and higher transparency, you’ll want to ensure you keep it in the best condition by using the right tools to clean it.


While glass is harder than acrylic, it can also be scratched. Natural gravel can contain mineral pieces which are harder than glass. If they are caught in between the glass pane and a tool or sponge, they can easily scratch the glass.


Stainless steel is often used as a glass-safe blade for algae scrapers. Stainless steel has a hardness on the Mohs scale of 6.5. If the blade becomes bent at the corners, it could scratch glass which falls between 6 and 7 on the scale.


Regardless of the tool, for the most part, there is a glass version and an acrylic version. Algae scraping blades for glass are made of stainless steel. Blades for acrylic are made of plastic. Sponges for glass are more coarse than the softer sponges made for acrylic. Most magnet cleaners allow for soft acrylic safe inserts.


Magnetic aquarium glass cleaner on a fish tank pane, with green and red plants blurred behind it and label text visible.

A magnet cleaner is a tool which uses two magnets, one on the inside of the aquarium and one on the outside. Both magnets are encased in a protective plastic casing. The inside casing and magnet has a piece of felt or thin sponge and sometimes a scraper blade attached to it. The magnets are placed on either side of the pane and as you move the outside magnet, the internal one with the felt and scraper moves with it. This allows you to wipe down the viewing panes without submerging your arm in the aquarium.


There are several popular brands of magnetic cleaners. Make sure you purchase acrylic safe inserts to use between the magnets if you have an acrylic tank.


White-and-blue floor squeegee with two replacement blades on a black surface, lit with purple highlights.

As we go over the methods for cleaning the panes, keep in mind the tool you’ll be using will depend on the material your tank is made of. Be sure to only purchase tools that specifically mark the material they are designed for.


  • steel blades with handle

  • plastic blades with handle

  • course sponge with or without handle

  • soft sponge with or without handle

  • hard bristle brushes

  • soft bristle brushes

  • ammonia-free glass cleaner

  • microfiber cloth

  • magnet cleaner


Method for Cleaning Aquarium Panes

Before you begin vacuuming your gravel and removing water, and before you replace your filter media, I recommend cleaning the viewing panes of your tank. As you scrape off and clean the algae that has accumulated, it should end up in your filter or in the water column. Then you can remove it with your media replacement and water change.


Two long black scrub brushes with blue and white scouring pads on a dark surface, lit with purple highlights.

Begin by wiping down the front pane. You can either use a hand sponge, a sponge with a handle attached or a magnet cleaner.


Start at the top of the pane and wipe from left to right top to bottom. Leave an approximately one inch margin at the corners and bottom of the pane.


Repeat this process for the two side panes and as much of the back pane as you can safely reach without disturbing equipment, plants, and decorations.


Cleaning the Corners

Next, you’ll clean the corners of the viewing panes. I do not recommend using a scraper, plastic, or steel to scrape the corners as the integrity of the silicone can become compromised.


Even if you have a glass tank, I recommend using a softer sponge, with or without a handle, and gently apply pressure to the corners as you wipe up and down. You can then wipe up and down right along where the silicone meets the pane as well. Recently, we have begun using soft bristle toothbrushes designed for super sensitive teeth. They have worked extremely well with cleaning silicone.


If the sponge is in contact with the silicone, apply less pressure with more passes. If you apply too much pressure, it could peel away older silicone.


Cleaning the Bottom

Cleaning the bottom of the glass pane where it meets the substrate requires some finesse. I would recommend a steel or plastic scraper as it will remove the most amount of algae with the fewest passes. This prevents increasing the likelihood of getting substrate caught in the tool and scraping the pane.


Start by applying pressure to the scraper about 1 inch above the substrate. Then push the scraper down into the substrate, removing the algae as you push down and in toward the glass.


Then relieve the pressure from the glass and pull the scraper up and out, towards the inside of the aquarium. If you keep pressure on the scraper while lifting up, it can trap substrae inbetween the blade and glass or acrylic as you pull it back up and then scrape the pane.


Repeat this "apply pressure down, relieve pressure up" motion starting 1 inch above the substrate as many times as necessary as you make your way along the entire bottom of the aquarium on all four sides.


Detail

After the front and side viewing panes have been cleaned from top to bottom and in the corners, you’ll want to clean around your internal equipment, if you have any. This equipment includes filters, heaters, powerheads, thermometers, etc., and is usually installed along the back pane. If the item is easily removed, like a thermometer, you can remove it, wipe it down, and replace it. If not, you can use a toothbrush or soft bristle narrow brush to clean next to and behind intake tubes, heaters, and powerheads.


I would also recommend using a bottle brush on the inside of your intake and output filter tubes after you shut your filter off for the water change. These areas can accumulate detritus and algae if they are not opaque.


If they are opaque, they can still grow bacteria on the inside which can slow filters if it allowed to accumulate.


Cleaning the Outside

Finally, polishing the outside of your tank is important to remove any water stains and keep the glass as clear as possible to allow the best viewing experience. Also, your photos will come out better with clear, polished glass.


First, spray a microfiber cloth with some ammonia-free glass cleaner. The glass cleaner must be ammonia free in case any residual aerosol gets in the aquarium. To prevent any contamination to the aquarium, spray the cleaner into the microfiber cloth from 5 feet away. Don’t spray the cleaner directly on the glass or acrylic. Then simply wipe the outside of the tank until it's dry and streak free.


A Soft Touch

Using the right tool to clean your aquarium glass or acrylic panes is key to preventing the over-application of elbow grease. Combining the right tool with a soft touch and some patience will prevent scratches and damage to the silicone, keeping your viewing panes looking clear and transparent for years to come. It is possible to buff scratches from acrylic tanks, but glass is a lot more difficult if not impossible. Preventing damage is much easier than removing it.


Be sure to keep up to date on the latest in aquarium cleaning technology. We sometimes get used to a particular method and forget to explore newer, easier options.


Photos
  • Boodleshire LLC 2022





 
 
 

Comments


Fully Insured
24/7 Support
Lab Grade Service
Lifetime Service Warranty
  • Facebook
  • Instagram
  • Youtube
  • LinkedIn

9913 Pflumm Rd, Lenexa, KS 66215

© 2025 by Boodleshire LLC 

bottom of page