Algae Control Guide

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A common, unwanted side effect of having a fish tank or aquarium is the growth of algae — an umbrella term for plant-like photosynthetic organisms that thrive in the nitrogen-rich environment of a fish tank.

While not harmful for fish, algae can obstruct the visual appeal of your tank.

fish tank algae remover

The most common form of algae resembles green or brown sludge. It collects on the walls of your tank and the surface of your water. If you have rocks or other items in your tank, it will also grow on their surfaces.

Thankfully, there are many things you can do to help control the growth of algae. Here we’ve gathered all the tips you need, so read on!

Preventative Measures for Algae Control

It’s much easier to try and prevent algae’s growth than it is to slow down once it’s running free.

Algae has a way of creeping up on you when you least expect it and exploding out of nowhere. So, to head it off at the pass, be sure to apply these little routines to your fish care schedule:

  1. Limiting how much you feed your fish is a great way to curb algae growth. Fish should typically be fed once a day, so get into the habit of monitoring how long it takes them to eat their daily allotment. Any leftover food will only act as fuel for your algae to grow, so instead, remove any extra floating around in the water, and consider dialing back the amount that you feed your fish, as they obviously don’t need it all. This should cut back on the excess nutrients in the water for the algae to feed off of.
  2. Limit the amount of light that reaches your tank. Algae produce energy via photosynthesis, which is the process of using sunlight to synthesize foods from carbon dioxide and water. Therefore, algae needs light in order to flourish. The more direct light that you allow into your tank, the more the algae will grow out of control.
  3. Do not overpopulate your tank. If you place too many fish in one tank, you will only increase the amount of waste present, which contributes to the amount of nitrogen in the water — another energy source for algae.

aquarium algae control

How to Get Rid of Algae That Has Already Grown

If you already have algae in your tank, don’t worry. It’s not the end of the world.

You can still get a hold of this problem by employing a number of different hands-on methods.

Skim the Algae Off of the Surface

How often you change the water in your tank depends on the kind of fish you have, how large your tank is, and any added elements like plants or other decorations that are present.

Typically, however, you should be changing between 10 and 15 percent of the water once a week.

Use this time to skim any excess algae off of the surface, as this will help beat back its strong presence until you can provide a more thorough clean.

Scrub the Sides of Your Tank

Once algae has started to grow in your tank, it will multiply rapidly. It will sometimes appear to even be crawling up the side of your tank over days.

An easy fix for this is to take a toothbrush and scrub the algae off the tank’s sides. Once it’s floating in the water, you can then skim it from the surface.

Don’t forget to throw away the toothbrush afterwards!

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Invest in an Algaecide

Algaecides are chemicals that impede the algae’s ability to perform photosynthesis, thus eliminating its main energy source. If algae can’t feed, it will die, which makes this method a great fish tank algae remover.

There are several different forms of algaecide, which can come in the form of tablets, liquids, or blocks.

You should probably try to save this method of algae control for last, because it will also affect the health of any live plants in your tank.

Invest in Algae-Eaters

Of course, you can always buy algae-eating fish! While it’s not the most effective option available, it does allow you a natural and effortless method of keeping your algae population under better control.

However, people who solely rely on fish to rid themselves of algae usually end up disappointed, as no one fish (or even two) will be able to consume enough to make any stark difference.

Here’s a video showing more details on aquarium algae control.

Final Thoughts

It’s impossible to completely eliminate algae from ever growing inside your tank. Algae is a sign that your tank is capable of fostering life, which is a good thing!

As long as your fish are alive and kicking, you’re bound to deal with this hassle on a semi-regular basis. However, if you follow the steps above, you will limit its growth and enjoy a cleaner tank.


What’s your favorite method for algae control?

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