How Do You Clean White Residue, Algae from Aquarium Glass

By Eddie Waithaka @aquariawise

How Do You Remove White Algae from Aquarium Glass

Every so often, you will notice grime forming on your aquarium glass, and you might be wondering how to get rid of it. This grime is usually a white residue or algae, more than any other form of glass smudge.

The white residue is called limescale that buildup on fish tank glass mostly around the top edge at the waterline. The residue can either be caused by calcium or magnesium carbonate, which is a result of the evaporation of hard water.

That said, while limestone is not always present in aquariums (or at least not too much of a nuisance), algae is more common and can be a real pain in the neck. Algae will creep up on anything it can hold on to, including the aquarium glass, if the conditions are right for its growth.

So, given the context, how do you remove white residue and algae from your aquarium glass?

Well, each have a different approach!

Remove limescale (white residue) from your fish tank with white vinegar, which is a weak organic acid and safe for use in aquariums. The vinegar (acetic acid) will dissolve the limescale (calcium or magnesium carbonate) seeing that it can be dissolved by any acid.

On the other hand, to remove algae from aquarium glass, you only need to scrape the glass. However its also important to note that the easiest and most effective way to stay ahead of algae is to not create an enabling environment for its growth, including too much light in the tank.

I have shared some more insight on this topic throughout this post, please read on!

How to Remove Limescale (White Residue) From Your Fish Tank

As I mentioned above, limescale or the white residue that forms in aquarium glass, especially in tanks filled with hard tap water, is calcium which forms as a result of evaporation and can be removed with vinegar (acetic acid).

There are several store-bought products made for the safe removal of lime (white residue) buildup from fish tank glass, but plain white vinegar is greener and a more affordable alternative.

To help you remove limescale from your aquarium glass with vinegar, follow this quick step to step guide.

  1. Relocate your fish into a holding tanks. To do this, you can either use a net or trap to catch your fish and move them into the new tank. Most importantly, make sure the parameters in the holding tank are stable and safe for your fish, the water quality should also be a replica of the water in the former aquariums. Failure to do this will cause a lot of stress or/and shock to your fish, and may even end in a few dead animals.
  2. Remove any plants and decorations and drain the tank completely.. Start by disconnecting any power sources from the tank, including filter, air pumps, heaters, and overhead lights, because you don’t want active electric power going to your tank while you empty the water. Removing decorations, rocks, wood, and plants will also make the draining process much easier. Drain the water either using a hose (siphon) or a gravel cleaner.
  3. Remove your substrate (gravel) if need be, though it’s not a must. Using a plastic dustpan works best for scooping gravel and then dumping into a holding bin. Usually, the hardest part is figuring how to get the pebbles without also getting a bucket full of water, so drain your tank completely. Also, let the water run out of your dustpan handle once you scoop the substrate from the tank before placing the gravel in the holding tank.
  4. Lay your tank down on a clean rug and pour vinegar on the grimy glass. The towel or area-rug you use should be soak-up any water that spills from the tank to ensure that nothing in your home gets damaged. You can even use more than one area-rug, depending on the size of your fish tank. Once it’s well placed, pour vinegar on the grimy glass and let it sit on there for 10 to 20 minutes.
  5. Scrab the glass with a non-abrasive pad or cloth till all the limescale is removed. It’s OK to Use a razor blade or algae scraper to remove stubborn lime patches on glass panels, but not on plexiglass and other acrylic materials because they scratch easily.
  6. Rinse your fish tank before you put it up again, this will aid in the removal of excess vinegar on the glass, which left to go inside the fish tank will mess with your water ph, albeit not harmful to fish.
  7. **Setup the clean tanks as before.**You will probably experience a mini cycle when you switch over, so keep an eye on your parameters, make sure the ammonia and nitrites remain at 0ppm, and the nitrates don’t rise too far above 20ppm. You’ll also want to check the ph, temperature, and make sure there are no chemical elements like chlorine in your water column.

How to Prevent Hard Water Stains (Limescale) on Aquarium Glass

As with everything undesirable in life, prevention is always better than cure, as such staying ahead of the white residue forming on your aquarium lid will save you a boatload of headache.

So exactly how should you go about it?

As we have already established, the main cause of white stains on aquarium glass is evaporating hard water, which leaves calcium residue on the fish tank lid. As such, the easiest way to keep the white grime at bay is using distilled aquarium water instead of tap water with traces of minerals like calcium.

You could also put plastic wrap over the glass, but you would need to replace it once every week or when needed. Sometimes you might even have to replace the wrap every time you feed your fish.

I’ve also seen some hobbyists using clear plastic food wrap to cover the top of their tanks, which will minimize the evaporation, plus limescale does not form on the wrap anyway. A clear mesh is also a viable alternative.

One final way you can reduce calcium buildup is regular tank maintenance. Ensure your filter is working properly and reducing free-flowing minerals in the water. Also, do regular water changes and monitor your water with test strips.

How to Clean Algae From Aquarium Glass

Algae is a way of life in freshwater aquariums and will cover almost every surface given the right conditions, to thrive in the fish tank it requires light, nutrients, and carbon dioxide.

However, no matter how much you try to limit its growth, you will always have some in your tank including on the glass.

Given that fact, then how do you clean algae forming on your aquarium glass?

I recommend scraping the algae off your glass using an algae glass scraper, which should remove most of the algae. Withal, exercise caution as you do not want to injure yourself, scratch or crack the glass on your tank.

Besides using a scrapper, please note that removing algae from glass will not prevent future growth, it’ll only give you time to remedy the enablers facilitating the growth.

For this reason, below is how to keep algae from forming in your fish tank glass.

How to Prevent Algae Build-Up on Aquarium Glass

The most effective way to keep algae off your glass permanently is to consider its growth wholesomely, which means stopping the algae from starting in your tank altogether.

The first and easiest way to do this is to starve the algae. Start by keeping your aquarium lights on only for the recommended 8 to 12 hours a day, then turn them off for the rest of the day.

Preferably, let the lights remain on during the day, then keep them off at night to mimic the normal diurnal-cycle. But if your fish tank has access to too much sunlight during the day, keep the lights off all days, plus consider moving it to a shaded part of the room.

Secondly, algae feed on nutrients like minerals in the water column, including nitrates, which is most times a result of leftover food, fish poop, and rotting plant debris. So, to further starve the algae, add a powerful filter in your tank, and clean your tank properly with regular water changes.

Lastly, add fish like bristlenose pleco, siamese algae eaters, and suckermouth catfish or inverts like nerite snails that consume large amounts of algae to keep the population in check.

Adding aquarium plants that compete with algae for nutrients such as nitrates and phosphates in the water column will also help.

In conclusion, when faced with a major algae problem, use a combination of these measures for quick and better results.

That’s all for this post.

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