Name: Crossocheilus siamensis
Origin: Southeast Asia
The Siamese Algae Eater is generally considered to be the best all-around algae eater available to aquarists. Unfortunately it is easily confused with other similar species (usually "False Siamensis" Epalzeorhynchus sp.), and is often mislabeled in stores. Most of the fish I've seen in Canada sold under the name "Siamese Algae Eater" are really Epalzeorhynchus sp. A relatively peaceful fish, especially when young, it can become agressive to its own species as it ages, and its quick, darting movements can stress out some more sensitive fish, such as dwarf cichlids or discus. A very hardy fish, it is easy to keep and feed, eating both algae and just about anything else put into the tank, such as flake food, pellets, live foods, parboiled vegetables, etc. It does a diligent job of removing algae from plants without harming them, as well as from decorations and aquarium glass. Considered by this aquarist as a necessity in any well-planted aquarium. Cover the tank carefully however, as these fish are strong jumpers.
These are the hardest working, most beautiful cleaner fish you can get. I think they are much more attractive than the false siamensis and CAE's with whom they are commonly confused. Once you know what to look for it, is easy to make a distinction. The main thing to look at as the stripe. True SAE's have a serrated stripe that runs all the way to the tip of the tail. I have 10 SAE's in my 380 liter and they are constantly looking for algae or leftover food to nibble on. They never stop! I highly recommend these to anyone with the room for them. They get quite large, I've seen some about 14 cm! They are a must for a planted tank, as they clean the leaves so well, but cause no damage to the plant whatsoever. They eagerly take flake food, but should always have some sort of vegetable matter in their diet, so if they run out of algae, supplement with sinking algae tabs, mine love them. SAE's are very peaceful toward other fish, but I've noticed mine can occasionally be territiorial to each other, although I don't think they have the ability to cause injury.
I have had my SAE for about 10 years. He has grown so big (about 13 cm and has outlived every fish in my tank. Although I have read that he is a good algae eater, mine is a big fat lazy opportunist. He eats more processed food and live food than all my fish put together and has a big fat gut. He or she is also very territorial and won't allow any of the fish to have a space of their own. I have a 300 liter tank filled with sweet little community fish, Angelfish, a Kribensis mother and some grown babies, and some Rams. He lays ownership to any spot that another fish wants. I do have to say that he doesn't allow other fish to fight. If he sees fish getting aggressive toward one another, he is right there to break it up. He is absolutely a pain in my tank, but I love him.
I would bet the people who have aggressive fish that do not eat algae are Chinese Algae Eater (Gyrinocheilus aymonieri). These fish are very commonly sold as merely Algae Eater. Watch out for its adult size, and temperament. The Siamese Algae Eater, (Crossocheilus siamensis) is an active and fast swimmer, which thrives best in schools but can also be kept alone or in pairs. It is a strong jumper and should not be kept in uncovered tank, because it will eventually jump. Siamese Algae Eaters often chase one another, but they never get hurt in these fights. As they are not aggressive, they can be kept in any community tank big enough. Their active behavior might stress some sensitive species like dwarf cichlids and prevent them from spawning. They should not be kept with red-tailed sharks (Epalzeorhynchus bicolor) unless the aquarium is large and well planted, because that species is very aggressive towards all its relatives. I have kept these fish in my 200 L community tank for years bacause this slender algae eating barb is the only known fish that eats the red algae which grows in my heavily planted tank from time to time.
We had problems with black bearded algae in our 85 liter tank. So we bought 4 SAE's when they were just a couple of centimeters long. They quickly grew to maximum size (12-14 cm), and we had to get a new aquarium. We bought a 530 liter aquarium, and the fishes are now very happy, I think. We have had no problems with black bearded algae after the SAE's moved in. Have in mind that they grow quite large, and should have plenty of space to move on. They are so incredibly fast, that I call them "my 4 small jet fighters". They are nice to other fish!
I have a school of seven SAE's in my 220 liter community aquarium. They range in size from about 6 cm to 8 cm. I believe these are about the most industrious algae eaters I've seen in my 55 years as a fish hobbyist. I originally purchased them because I read somewhere on the internet that they were the only species that ate what has come to be known as black bearded algae, which is an unsightly pest that is very difficult to get rid of. I had this scourge all over some driftwood and all over my live plants, and it was one of the factors that led to the demise of many of my plants. The SAE's went to work the instant I put them in the tank, and within a few weeks the driftwood looked like it had just come from the processor - it sparkled a bright brown color. They also went to work on the plants when they got tired of polishing the driftwood. Within a few days those leaves that were not destroyed by the algae began to look greener and brighter. The algae was almost gone, and there were no residual holes where the SAE's had been feasting. Since this aquarium is located next to my computer, I get to spend a lot of time watching the fish, and I have never seen the SAE's resting. They constantly forage on every surface in the aquarium. I have found these little custodians to be a peaceful and most useful addition to this community aquarium, which is populated with several species of near adult rainbowfish, adult Congo tetras, adult emperor tetras, and several half grown Apistogramma species.