- Algae eating fish and invertebrates


Algae eating fish and invertebrates

Author: Yeo-Hoon Bae
Last Updated: Nov 5, 2009

Your tank is full of algae and you want to get rid of it. Are you wondering if you can fix this easily by adding some species that will eat the algae in your tank?

There are couple of fishes, shrimps and snails that are capable of eating algae. Unfortunately, they are not substitute for fixing the cause of the algae in the first place.

You should look into the following first:

  • Do you have too much light?
  • Do you have too much nutrients?
  • Is your CO2 level fluctuating?

  • Nevertheless, algae eating species will help control the amount of algae present in your tank. Just make sure they are not introduced just for the sole purpose of getting rid of algae.

    Here are some of the common species that will eat algae. You should keep in mind that most tanks will not have enough algae to keep them alive - you will need to supplement their diet with some additional food. Some of them eat normal fish food, but almost all of them will eat blanched vegetables, especially blanched zucchini and spinach. Algae wafers work too.

    Siamese Algae Eater (SAE)

    Do not be confused with Flying Fox which looks similar but with different characteristics which makes them less desirable for your community tanks. SAEs are peaceful and are good algae eaters. They grow up to 6 inches so you will need a decent sized tank - at least 30x12 inch footprint. Once they hit around 4 inches, they will not eat algae as well. Most stores will sell them at 2 inches in size, so if you are looking for a long term solution, this may not work for you. They will eat variety of algaes but I have never seen them eat long strands of hair algae. If they are hungry, they will eat black beard algae. They are often suggested as a schooling fish, and if you have more than one, they often swim together. But unlike most schooling fishes, SAE can be kept in singles.

    Bristlenose Pleco

    These species of plecos are popular due to their limited size. Common pleco often exceeds 12 inches in size hence they are not suitable in most aquariums. Bristlenose plecos rarely exceed 6 inches and often less hence much more suitable to be kept in smaller aquariums. I kept them in a tank as small as 30x12 inch footprint and was successful at breeding them alongside other peaceful species. They will do a great job in eating most algae that grows on hard surfaces and flat leaves of plants. I've never seen them eat hair algae or black beared algae. There is a myth that Bristlenose plecos need driftwood in their diet. I'm not sure if this is true or not, but all of my tanks that held Bristlenose plecos had driftwoods in my case.

    Otocinclus (also known as "Oto")

    Otos are very peaceful and stays small (2 inches). They do a great job in eating algae but unfortunately only really soft early form of algae. Diatoms (brown) are one of their favorite meals. If your tank is infested with hair or black beard algae, do not buy this fish to clean those - Otos don't touch those algaes. Just about every specimen in the store are wild caught and due to the way they are caught in the wild, they are very very sensitive during the first month or two. Don't be surprised if you loose a large percentage of Otos after a month. Once you manage to keep them alive for few months, most likely you have a healthy specimen and will keep your tank clean for many years to come. They can be kept in a small tank such as 5g.

    Rosy Barb

    This species is good for hair algae. They are schooling species, hence you should keep at least 6 of them in the same tank. Don't let the small size fool you at the store, these guys will grow to at least 3 inches, often exceeding 4 inches, so plan accordingly. They will become much larger than your cute little tetras. If they are kept in smaller numbers, they can become nervous and become more aggressive against other fishes in your tank. Not a good idea to keep them with slow moving fishes featuring long fins.

    American Flag Fish (also known as Florida Flag Fish)

    Similar to Rosy Barb, they are great for hair algae. Unfortunately, they are also more aggressive and have tendency to fin nip other species with long fins, so you should keep this in mind. Also some AFF are known to eat variety of plants, especially young plants so you should keep your eye on these guys after introducing them into your tank. Will work better in a tank with more aggressive species.

    Amano Shrimp

    This is the best algae eating shrimp known to the aquarium hobby. They will grow close to 2 inches. Unfortunately, they are shrimps - they will malt as they grow. This means there will be times when their skin will be soft and most semi-aggressive fishes will eat them easily. If you have a lot of plants in your aquarium, you will be ok. They can be kept in a small tank such as 5g. They are great at finding any form of food including fish food! Don't overfeed aquarium tanks with these shrimps as they will excel at finding those and consume them. Then, they will not eat algae as much! These guys do not breed in cold water, so that could be either plus or minus depending on what you need.

    Red Cherry Shrimp

    Although not as good as Amano shrimps, they still do a pretty good job. A bit smaller than Amano shrimps, at just over 1 inch when mature. Once again, presence of lots of plants is desirable. They can be kept in a small tank such as 5g. These guys will breed easily in your aquarium tanks. If you have lots of hiding places for the little hatchlings, they will survive. These are one of the easiest shrimps to keep in the aquariums.

    Ramshorn Snail

    This snail species stay small, rarely reaches 3/4 inches in size. Both fish and shrimp eggs are safe hence it can be kept in most tanks where natural predators of snails don't exist. Variation includes black/brown and red. Red snails have recessive genes so if you mix them with more common brown/black kinds, offspring will also feature common colors. They can be kept in a small tank such as 5g. They will breed easily and if you overfeed, they will take over your aquarium. You have been warned!

    Nerite Snail

    One of my favourite algae eating species. These snails only eat algae, mostly diatoms (brown) and micro-algae, although some have reported that theirs eat hair type algae as well. My Nerite ate the dreaded Black Beared algae. If they run out of algae to eat, they will slowly die so do not introduce them in a new tank. For this reason, it is not wise to overstock the tank with these snails. Tank with lots of existing algae would be ideal. They are plant safe - not known to harm any plants. They will grow to around 1.5 inches. They are extremely hard to breed in fresh water - so it is not likely that you will end up with many of these just by keeping them in your aquarium. They can be kept in a small tank such as 5g.

    Your hands, fingers and tooth brush!

    Believe it or not, this is one of your best means to get rid of algae!

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