How to get rid of algae in an aquarium?

For any aquarium owner, algae is the most dreaded problem. Above all, it's not very aesthetic, and it can block some of your fish in their movement.

There are simple ways to prevent and get rid of this algae in the aquarium. Read our micro-guide to learn how.

Algae is a " basic " plant that can make its own food via photosynthesis, from light. These aquarium algae are usually very small, although they are part of a huge group ranging from those tiny single-celled algae that cause green water to much larger algae.

Algae were among the very first forms of life on earth and are present today on all continents, terrestrial and marine. They can tolerate extremely variable conditions, ranging from freezing to boiling, fresh water to saltier than the sea, and have adapted to evolve and inhabit virtually anywhere on earth. In our aquariums it usually manifests as a green coating on glass and decor, but it can also take many other forms.

Where do algae come from?

Algae can be introduced into an aquarium on the leaves of plants or in the water of fish bags, but even in aquariums that have been set up and completely sterile with no plants, fish water, or other life forms, algae can still begin to develop.

Algae spores can also be airborne and are everywhere we humans are. Whether it's a coldwater, tropical, or saltwater aquarium, or even a barrel of reverse osmosis water, if light can get to it, algae will grow.

How to stop algae?

You would not be able to completely stop algae growth in your aquarium unless it is kept in complete darkness at all times. However, there are many ways to control it.

A. Cut the lighting

If your aquarium contains live plants or corals, they will need the lights on for at least eight hours a day, but no more than twelve. If you don't have anything that actually needs light to grow and you have bad algae, try turning on the lights only when you're there in front of the tank, looking at it.

Optimize aquarium lighting

Fish don't care about ambient light (many species prefer low light), so your fish won't suffer and you'll get less algae as a result. For planted and reef aquariums, make sure you don't exceed 12 hours of light per day and don't use more light than necessary. Some LED lights can be dimmed, faded and faded, and aimed specifically at where the plant or coral is, meaning less light is wasted and less light spills onto the front glass , causing harmful algae.

B. Add algae eaters

Mother nature has many allies who will graze and consume algae for you. For freshwater and saltwater, an army of snails, shrimps and algae-eating fish can be deployed to graze on algae for you, helping to control it, get into inaccessible places and destroy it. snacking 24 hours a day. . Many species also require algae in their diet.

Add algae eaters when the first growths of algae become visible and they will help control it. Algae eaters will not eat all types of algae (more on this below) and will also ensure that their diet is supplemented with species-specific foods, such as shrimp food, or seaweed wafers or tablets.

Proprietary algae feeds will also contain essential vitamins for algae-grazing shrimp and fish. If the algae is eaten entirely, the algae eaters will get hungry, so they will need regular feeding, just like your other fish.

C. Solutions to limit algae

In addition to needing light, algae also need nutrients to thrive. In the aquarium, algae nutrients can occur in the form of nitrates and phosphates. Nitrate is the byproduct of biological filtration and accumulates, and phosphates can come from fish food, fish waste and tap water.

Control nitrates and phosphates with disposal resins nitrates and phosphates and you can fight algae. Plants naturally take up nitrate and phosphate as food, and some aquatic plant growers and aquascapers actually add nitrate and phosphate to their planted tanks, but that's for another article.

Nitrate and phosphate free water can also be created using a reverse osmosis unit, and ideally a deionizer, to ensure that the changed water is free of nitrate and phosphate.

D. Perform water changes

Water changes are a very simple way to control harmful algae. As noted above, nutrient levels can be lowered by water changes, but it also gives you an excuse to physically remove algae during maintenance. As part of your weekly routine, wipe algae off glass, scrub plant leaves and decor, then siphon away algae scrapes with a gravel vacuum cleaner .

Clean your filter sponge in the tank's dirty water bucket, then filter maintenance, tank maintenance and algae removal can be done in one go. Changing the water helps physically reduce the amount of algae spores in the aquarium, and old tank water can be reused to water plants in your home or garden.

When seaweed is not seaweed

One of the most harmful types of algae in the aquarium, slime algae, is not an algae at all. Belonging to the genus Cyanobacteria, as its scientific name suggests, slime algae is actually a bacterium, not an algae at all, but it grows and behaves similarly, smothering surfaces and thriving only in reservoirs with light and nutrients.

The downside of this harmful bacteria is that algae eaters have no desire to eat it. In fact, they won't touch it, and it may even be mildly toxic to some life forms. It is usually blue/green in freshwater tanks and red in marine tanks.

The good news is that cyanobacteria can be treated like conventional algae, by scraping and brushing them from surfaces and then physically siphoning them off. Regular maintenance is essential with Cyano, along with plenty of water changes and a strong water flow to avoid the dead spots this mud prefers.