Follow These Aquarium Maintenance Guidelines to Get Rid of Excess Algae

We all want our aquariums to look beautiful. It’s every aquarist’s goal to have a vibrant, colorful, lively aquarium to look at and excite the senses. However, if algae growth gets out of control, your aquarium could be left looking slimy, murky, and disgusting. Quick fixes like siphoning won’t help, either—to truly rid your aquarium of nuisance algae problems, you have to apply aquarium maintenance habits that resolve the underlying issues.

Whether you’re dealing with filamentous “matted algae,” planktonic “pea soup algae,” or branched algae like Chara, excess algae growth is a recurring problem and you need a long-term plan to fight it. Here are the three main tactics you should use to eliminate persistent issues with any of these types of algae: reducing excess light, eliminating excess nutrients, and introducing competition.

For a more comprehensive look at maintaining your aquarium, see our guide here.

Reduce Excess Light

Like all greenery, algae thrive off of light and needs a lot of it to grow and survive. If you’re having a lot of problems with algae growth, the problem might be that you’re saturating your tank with high light levels. This creates an environment that caters to the algae and helps them grow, filling your tank with murky water.

Cutting back on lighting can be an effective first step in using aquarium maintenance to combat algae levels.

If you don’t have plants or coral in your aquarium that rely on lots of light, cut lighting to four hours per day or less. Algae will struggle to get the light they need. Some of your fish may even enjoy the low light conditions, as well. For example, cichlids show good color in dim, ambient light.

However, aquarists with plants in their aquariums still need to maintain high light levels. In that case, a popular method for dealing with algae growth is to turn off the lights for one or two hours in the middle of the day. Plants will be able to deal with this, but algae will have their growth interrupted.

Finally, watch out for direct sunlight. Exposure makes algae grow wildly. If your aquarium has to be near sunlight, try blocking it out with backing paper or a structured internal background.

Eliminate Excess Nutrients

Another factor that fuels algae growth is excess nutrients. Algae grow by consuming nutrients such as phosphates and nitrates, which are produced by your aquarium inhabitants including fish, crustaceans, and mollusks. Poor aquarium maintenance results in excess nutrient buildup which encourages excess algae growth, so correcting those aquarium maintenance issues is key to eliminating algae.

Factors that contribute to excess nutrient buildup include:

• Inadequate water changes and poor aquarium maintenance
• Poor water circulation
• Using an improper water top-off source such as tap water
• Using a low-quality sea salt mix
• Lack of natural algae-eating predators

To start, use test kits to get readings for your phosphate and nitrate levels. This’ll give you a better idea of what you’re dealing with. Then tackle the problem with these potential aquarium maintenance fixes:

• Use a protein skimmer to remove excess dissolved organic compounds (DOCs) that algae feed on.
• Perform water changes to help dilute the nutrients, especially in smaller systems where larger or more frequent changes are practical.
• Only top off your water supply with reverse osmosis (RO) or deionized (DI) water.
• Alternatively, use purified water as well as nitrate and phosphate removal resins.
• If algae persist, test for elevated levels of silicates. If excess silicates are present, use a deionizer to remove them.
• Alter your feeding habits to prevent overfeeding, which contributes to excess nutrients becoming an ongoing problem.
• Consider removing big, messy fish that produce lots of phosphate and require bigger, dirtier filters to maintain.

Introduce Predators and Competition

Finally, you may want to enlist some help fighting your algae problem. Add inhabitants that either eat algae or compete for the same resources as algae to help keep them from being able to spread throughout your aquarium.

Competition for Nutrients

There’s a wide variety of organisms available that you can add to your aquarium that will outcompete algae for nutrients and leave them unable to get a foothold in the tank. For example, aquatic plants will take up nitrates and phosphates as well as trace elements and macros that otherwise would feed algae. Heavy planting is an effective step in aquarium maintenance to combat excess algae.

Similarly, macro algae like Caulerpa, seaweeds, and kelp also use nutrients in the same way. You can place them in a refugium, which is a secondary tank connected to your aquarium. The refugium contains macro algae, invertebrates, and other organisms that can’t stay in the main tank since your fish would just eat them. When water passes through the refugium, those organisms consume nutrients and remove them from the water column, depriving algae of the nutrients they need to grow.

Predators Who Eat Algae

There are also many species of organisms that actively feed on algae, help you keep its growth under control. These fall into a few different categories, including:

• Fish—The lawn-mower blenny and bicolor blenny remove algae from surfaces like glass. Tangs and Surgeonfishes can keep both micro algae and macro algae in check. Other fish you may not normally consider include mollies and angelfish.
• Herbivores—Many snails like turbos and nerites will eat algae while patrolling your tank. Small hermit crabs like the opportunistic blue-legged hermit crab are prized by some reefkeepers for how well they seek out and crop algae.
• Detritovores—Starfishes, marine worms, and sea cucumbers all also contribute to removing excess algae depending on the type.

The important thing to not here is that you need to pay attention to what types of algae each of these eat, whether that matches the types of algae you’re having problems with, and whether these inhabitants will otherwise fit in well with the rest of your aquarium.

Consult a Professional for More Aquarium Maintenance Tips

Maybe you’re having trouble figuring out which of these is causing your algae issues, or what aquarium maintenance solution would be appropriate to try. Maybe you’ve tried some of these and are still having trouble, or want to make sure you prevent future algae problems. In these cases, it’s important that you consult an expert to get a professional opinion.

We here at Living Art Aquatics have been designing artistic seascapes and performing professional aquarium maintenance in Crystal Lake, IL and the Chicago area for decades. We have the professional expertise necessary to accurately evaluate your algae problem and prescribe an aquarium maintenance solution that actually works. Give us a call today at (847) 737-5151 and make your algae issues a thing of the past!