Choosing the Right Algae-Eater by the Type of Algae in Your Tank

There is nothing worse than waking up to feed your fish and finding your entire tank covered in a layer of green. Algae is a common problem in freshwater aquariums but it is actually a fairly simple problem to solve. The more you understand what causes algae to grow, the better you can prevent it from happening. It will also help you to read up on algae-eating fish that can help you to keep your tank clean and algae-free.

Why Does Algae Grow in Home Aquariums?

Algae is a living thing and, as such, it requires certain nutrients to grow. There are many different types of algae out there, but they all have the same basic requirements. First and foremost, algae need water in order to thrive. Next, algae need plenty of light. Like any photosynthetic organism, algae use light as an energy source to fuel its growth. If you have live plants in your tank, you probably also have a pretty good lighting system and you probably leave it on for 8 to 12 hours a day. Too much lighting or lights left on for too long can lead to excess algae growth. This is a common problem in tanks that are placed too close to a window, even if the tank doesn’t get direct sunlight.

In addition to light, algae also require certain nutrients in order to grow. The main nutrients algae needs are nitrogen, phosphorus, and potassium. These nutrients are abundant in most aquariums because they come from things like uneaten fish food, fish feces, and even the metabolism of the beneficial bacteria that help to maintain the nitrogen cycle in your tank. You may also be surprised to learn that most tap water is very high in phosphorus. When your tank has an abundance of these nutrients, you are more likely to experience rapid algae growth. Sometimes having live plants in the tank can help with this because they’ll compete with the algae for some of the same nutrients.

Many aquarium hobbyists assume that algae growth in their tank is a sign that the tank is dirty. While algae might make your tank look dirty, it is actually more likely to thrive in a tank that is clean. The more thoroughly you clean your tank, the more likely you are to see some algae growth. A simple tip to avoid algae overgrowth following a tank cleaning is to leave just a little bit of it behind – the existing algae will use up the nutrients that are available, preventing them from being used to fuel the growth of new algae in your tank.

Types of Algae in Freshwater and Marine Tanks

When you think of aquarium algae, you probably picture a fluffy green growth. While this is certainly one kind of algae, there are actually many different types that you could find in your aquarium. Here is an overview of the most common types of aquarium algae:

• Brown Algae – Most likely to develop in new tanks, brown algae thrive in low light conditions and in water that is rich in nitrates and phosphates. It typically forms in fluffy spots on substrate, rocks, glass, and tank decorations.

• Green Hair Algae – This type of algae forms wispy, hair-like growths that can reach 1 inch in length, or more. Hair also usually grows in high light conditions with low CO2 and nitrate levels.

• Brush Algae – Often found growing on the leaves of slow-growing plants and inside tank filters, brush algae is often the result of high kH or low CO2 levels.
  

• Blue-Green Algae – Also known as cyanobacteria, blue-green algae thrive in dirty substrate and filters as well as in tanks with poor circulation. It also does well with low nitrites and high levels of other nutrients.
• Green Spot Algae – This type of algae forms spots on the glass of your tank and on plant leaves. It usually grows in low CO2 and low phosphate levels or in tanks where the lights are left on too long during the day.
• Staghorn Algae – This algae forms strands that look like antlers and they are typically dark green to grey or black in color. Staghorn algae prefer low C02 levels as well as dirty substrate.
• Green Water – This is a sign of excess light or high ammonia levels – it could also indicate high levels of other nutrients or overfeeding (which could lead to the buildup of nutrients as the extra food is broken down).

The type of algae that grows in your tank can tell you certain things. For example, an excess of blue-green algae means there are too many nitrates and phosphates in your tank while black algae tend to grow in areas with poor water circulation. In the next section, you’ll learn how to choose the right algae eater for your tank based on the type of algae you have.

The Top Algae Eaters for Your Tank

Algae eaters aren’t just fish – they can be anything from snails to aquarium shrimp, as long as they feed on live algae growths. Getting rid of algae in your freshwater tank can be tricky and you need to be careful what method you use – commercial water treatments can sometimes do more harm than good by throwing your water chemistry out of whack. If you know what type of algae you have growing in your tank, you can choose an algae eater that tends to target that specific type of algae – here are some ideas to get you started:

• All Types – Twig Catfish, Siamese Algae Eater, Otocinclus Catfish, Bristlenose Pleco, Mollies, Nerite Snails, Ramshorn Snails, Mystery Apple Snail, Malaysian Trumpet Snail, Cherry Shrimp, Ghost Shrimp, Flying Fox, African Cichlids, Chaetostoma

• Brown Algae – Otocinclus Catfish, Amano Shrimp

• Green Hair Algae - Otocinclus Catfish, Nerite Snails, Amano Shrimp, Ghost Shrimp, Siamese Algae Eater, American Flagfish, Flying Fox

• Green Spot Algae – Bristlenose Pleco, Nerite Snails, Mystery Apple Snail

• Brush Algae – Mollies, Amano Shrimp, Siamese Algae Eater, Flying Fox,

• Blue-Green Algae - Mystery Apple Snail

One thing you need to keep in mind about algae eaters is that they may not be able to survive on live algae growth alone. In many cases, you’ll need to supplement your algae-eater’s diet with sinking wafers or pellets and fresh veggies. Be sure to do your research before you buy an algae eater to ensure that you can provide for its needs in terms of tank requirements. As with any type of fish, you also have to be careful not to overfeed your algae eaters because that could exacerbate your algae problem. The best rule of thumb to follow is to only offer your fish as much as they can eat in about 2 minutes and feed them two or three small meals per day.

Algae is a common problem in the home aquarium and, though it can be a nuisance, it is generally not something you want to get too worried about. If you are concerned about the algae growth in your tank, try reducing the amount of lighting or test your water to check for excess nutrients. You can also use the information provided above to choose an algae eater than will clean up the algae for you.