Best algae eaters for a tropical fish tank

Noone likes a green, algae-filled tank, except for these guys that is! Here’s the Swell Guide to the best algae eaters for your aquarium.

Bristlenose catfish, Ancistrus spp.

Bristlenose catfish from the genus Ancistrus are brilliant all-round algae eaters. They don’t get too big like Common and Sailfin plecs do and the tank bred ones are hardy with regard to pH and temperature. They’ll even breed in the average community tank. Perfect for all tropical aquariums over 75cm in length. Recommended.

Midget sucker catfish, Otocinclus spp.

Midget sucker catfish as they are also known are the smallest members of the Pleco family, making them perfect for nano tanks and planted tanks. At just a few cm in length, you can employ a small army of six or more to rasp away at wood, rocks and plant leaves. They can be delicate when first imported but once settled they’ll do a great job of algae-eating and you’ll hardly know they’re there.

Black mollies, Poecilia sphenops

Black mollies aren’t on the radar of many algae battlers but those upturned lips are great at rasping algae from all surfaces including wood, rock and plant leaves. They do prefer hard water and even salty, brackish water, but Platies and even Guppies do a similarly good job. You’ll be surprised!

Siamese algae eater, Crossocheilus siamensis

Siamese algae eaters, Crossocheilus siamensis

Siamese algae eaters are wonderful for eating green hair algae and are also often prescribed for eating nuisance Black Brush algae. The downside is their eventual size of six inches and the fact that they should really be kept in groups in long, stream-styled aquariums. They can jump too. But definitely an “A” list algae eater. 

World’s best algae eater, Crossocheilus reticulatus

It’s a big title to live up to but about 20 years ago a plain-looking species called Crossocheilus reticulatus was marketed as World’s Best Algae Eater by its suppliers. A relative of the Siamese algae eater, it is indeed very good, but like the Siamese, it also prefers to be in shoals in big tanks. If you have a big tank and you see some for sale – definitely worth a try. 

Sucking loach, Gyrinocheilus aymonieri

Also known as Chinese algae eaters, Gyrinocheilus aymonieri are very hardy and can also be kept in unheated aquariums. As small fish, they are busy, very effective algae eaters. The problem is they grow larger and more territorial, so although a good short term fix, they may be problematic in the long term and only suitable then to be mixed with tough fish in large tanks. A golden variant is also available.  

Garra, Garra spp.

Garra species also come under the “sucking loach” catch-all and come from rivers in streams in South East Asia. Most are plain but some are colourful and some even develop horns on their heads as they mature. All are very good algae eaters although they suit fast-flowing, cool, stream-style aquariums and can be territorial as they grow and mature. 

Algae eating shrimp, Caridina spp.

The Algae eating shrimp is Caridina multidentata, also known as the Amano shrimp after Takashi Amano, the man who introduced its use and algae-eating benefits to the wider fishkeeping world. It’s the perfect algae eater for nano tanks and planted tanks which don’t contain big fish, working tirelessly, 24 hours per day. Its also often combined with Otocinclus or even Siamese algae eaters in larger planted tanks and many people who keep them for the time instantly fall in love with them.

There are dozens of other tiny freshwater algae eating shrimp too including Cherry shrimp, Crystal reds and all their variations, and all make wonderful but tiny algae eaters. Being invertebrates, they bring another dimension to the freshwater aquarium.  

Posted by on

Jeremy Gay is an author, lifelong fishkeeper, and aquatic specialist. He's a former editor of Practical Fishkeeping Magazine, UK editor at Reefbuilders, a former aquatic store manager, and has collected fish in Sri Lanka and the Amazon. He's been on tv and radio, contributed to Koi Carp and Gardeners World magazines, been a product tester, a judge, and a product developer. Jeremy is here to guide and advise you on all things tropical, pond and marine, from set-up to stocking, health, feeding to breeding, as well as solving many common fishkeeping problems along the way.

Add your comment

* Required fields