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Blennies for Algae Control in the Saltwater Aquarium

Saltwater

September 28, 2020

Keeping your saltwater tank free from nuisance algae can be a challenge but it is not an impossible task. In fact, the solution may be simpler than you think – just add a few algae-eating fish to your tank! While you may be familiar with some of the more popular freshwater varieties of algae eaters, you may not be as familiar with the options for saltwater tanks. One of the most popular and effective saltwater aquarium algae eaters is the blenny.

What Are Blennies?

The name blenny is given to a large group of small fishes belonging to the suborder Blennioidei. There are over 800 species of blenny that can be found in marine, brackish and freshwater environments. For the most part, these fishes remain small – up to three inches in length – and they are known for their elongated, bodies and their tendency to burrow into the substrate. What makes these fish unique is the fact that their dorsal fins are often continuous, running all the way down the back. The tail fin is often rounded, though some species have a forked tail (like Meiacanthus astrodorsalis, the forktail blenny). These little fish can be extremely beneficial in removing microalgae from the tank but they can be very territorial so it is recommended that you only keep one species per tank.

Recommended Species

There are many different species of blenny to choose from, but some are more highly recommended for the home aquarium than others. You will find a list of recommended species below:

Bicolor Blenny

Bicolor Blenny (Ecsenius bicolor) – This blenny is half orange and half blue-brown and it grows to a maximum length of 4 inches. These fish are fairly peaceful by nature, but they do have a tendency to pick on other blennies and small gobies. This species is a great addition to reef aquarium, though they can do some damage to corals in smaller set-ups so they are recommended for a minimum tank size of 30 gallons.

Black Sailfin Blenny (Atrosalarias fuscus) – As suggested by its name, this species is black in color and reaches a maximum length of 4 inches. These fish require plenty of live rock in which to forage and their diet should be supplemented with fresh vegetable matter. This species tends to target hair and string algae as well as other forms of microalgae.

Canary Blenny (Meiacanthus oualanensis) – This semi-aggressive species can achieve a length up to 5 inches and it is known for its bright yellow coloration. Canary blennies are omnivorous which means that they will feed on microalgae but their diet should be supplemented with some meat-based foods.

Striped Blenny (Meiacanthus grammistes) – Another omnivorous species, these blennies are semi-aggressive and grow up to 5 inches in length. The striped blenny has a white body ornamented with alternating black and yellow stripes.

Tail Spot Blenny (Ecsenius stigmatura) – This species of blenny is very small and peaceful, growing only to about 2 ½ inches in length. These fish have dark red bodies with a black and yellow band running below a very large eye on either side of the head. Tail spot blennies require plenty of hiding places as well as live rock from which to graze on algae.

Other Tips for Algae Control

The key to preventing algae from ever becoming a problem in your saltwater tank is to limit the amount of nutrients which feed it. Algae requires both food and light in order to thrive, so be sure not to place your tank somewhere where it will receive a lot of direct sunlight. Additionally, you should keep the water in your tank well filtered and clean so that phosphates and other chemicals which provide nutrients for algae do not build up. One easy way to do this is to install an EcoBio-Stone in your tank. EcoBio-Stones are infused with beneficial bacteria as well as the nutrients they need to reproduce and thrive in your tank. These bacteria, once introduced into your tank, will establish and maintain the nitrogen cycle which is how waste products are converted into less harmful substances. In doing so, your tank water will be kept clear and free from algae.