S.A.E.: A Fish Worth Its Weight In Gold

In the rivers of south-east Asia lives a very plain-looking fish, one that most aquarists would ignore if it wasn’t for Dr. Baensch’s discovery that it eats hair algae. In fact it is considered to be the best algae eater available. I am speaking of the Siamese algae eater (Crossocheilus siamensis), known to wired aquarists simply as SAE.

I first encountered this fish at a store when I was setting up my large (1.5 m long) planted community tank. It was to be my Amazon tank. The plants and fish had to come from the Amazon region or at least from South America. That was the theory. Since Siamese algae eaters are from the other side of the world, I just considered them neat and was glad that the store had them.

A few months later I started running into a familiar problem with new tanks: algae. I figured I had just about all types of green algae. My Amazon swordplants were covered in a carpet of algae and weren’t growing. I tried increasing the plant density with mixed results. Hornwort first became a weed that I had to remove weekly, then a small type of Salvinia exploded on the surface of the tank, followed by the giant duckweed (Spirodella polyrhiza). These fast growing plants kept the algae in check, but also provided shade for the swordplants. I needed something that would eat the algae, not just compete with it for nutrients.

As part of my Amazon fish collection I had a pair of whip-tailed catfish (Rineloricaria sp.), five Otocinclus affinis and two clown plecos (Peckoltia vittata). It turns out they weren’t eating enough algae. The otos fattened themselves on algae, then died looking emaciated (selective algae eating perhaps). I still don’t know what the whip-tails eat in my tank, for they are strictly nocturnal and freeze as soon as a light goes on. The clown plecos kept two pieces of driftwood very clean and polished. In fact they are great wood eaters.

Fellow club members suggested that I add a few bristle-nosed plecos (Ancistrus sp.). They also spoke very highly of its algae eating abilities. My reference books agreed, so I overcame my aversion to the fish (I find the bristles on the head simply revolting) and took a fully-grown male on loan. I also went to my favourite fish shop to get more bristle-noses as reinforcements. There was only one, so off to another shop for more. It was then that I found a tank full of Siamese algae eaters.

The algae eaters were quite small, only 3 cm in length, so I bought ten. My algal problem was so bad by now that I didn’t care that the fish were not Amazonian. I set up the new fish in a quarantine tank and spent a few hours cleaning the big tank. I removed every leaf that had algae on it, cleaned the driftwood and glass panes. I kept the worst leaves in a bucket of water to feed the new fish. That’s when I was most pleasantly surprised. I would add a few leaves to the quarantine tank in the morning, and by the time I would return from work the leaves would be spotless! The SAEs were so efficient I almost ran out of algae-covered leaves during the two-week quarantine.

When I added the bristle-noses and the SAEs to the big tank, the algae were making a slow return that ended on that day. The next day the tank was virtually algae free. The bristle-noses took to a large piece of driftwood, with many hollow branches, and disappeared. Meanwhile the SAEs doubled in size in three months, and now after 11 months they are over 10 cm long. I was warned that they get territorial, and I’ve noticed that they will push one another out of the way on occasion, but I haven’t seen any real fights. In fact the fish are quite gregarious and like to sun themselves at the front of the tank. It is quite a sight to see seven of them lying on the sand at the front of the tank, bodies aligned with the current, enjoying the winter sun.

By now you are probably wondering what SAEs look like. If you have access to a copy of The Optimum Aquarium by Horst & Kipper, turn to page 125 and skip the rest of this paragraph. If you have access to the Internet, check out Liisa Sarakontu’s home page at http://www.hut.fi/~lsarakon/, she has a good article on algae-eating cyprinids with identification tips and hand-drawn sketches.

SAEs are very similar to the flying fox (Epalzeorhynchus kallopterus) and were until recently placed in the same genus. The scales on the back have dark edges, giving the fish a reticulated appearance. They do not have the coppery reflection above the black longitudinal line as the flying fox, and unlike them have only one pair of barbels. Their more robust shape, clear fins and reticulated backs make them easy to spot when mixed with flying foxes.

According to my sources, nobody has managed to breed SAEs in an aquarium. I find this a little surprising because I’ve noticed two of my SAEs acting as if they were courting. They picked a fork at the base of a large piece of driftwood and remained there for a few days. The others were chased away. Unfortunately it was impossible to see inside the fork, so I couldn’t verify if there were eggs there, or if anything else was going on. At that time also, two of the bristle-noses had paired and the male was guarding a clutch of eggs inside the same driftwood. Who knows if the events were related.

One thing I find unusual is how the fish changes colour when there is any posturing going on. My experience with tetras, cichlids, and bettas is that the fish colour up and stretch their fins, looking quite impressive. SAEs become pale instead. Their black stripe fades to almost the same colour as their body, they wiggle and dash forward in mock attacks, with no injuries or undue harassment resulting from this. Usually two fish square off, do their posturing and then go on with life.

As for food, they seem to eat anything. Algae of course, frozen bloodworms, frozen brine shrimp, flakes, sinking pellets, freeze-dried tubifex, and boiled zucchini. They feed regularly with the rest of the fish in the tank, sometimes too eagerly, yet the algae is mostly absent even in winter when the tank can get up to two hours of direct sunlight on the front pane. I don’t think they clean the panes or the driftwood, the bristle-noses do that. SAEs seem to specialize in plants as I frequently see them mouthing the leaves looking for algae. They will uproot young plants when cleaning them, and I’ve seen them digging very shallow burrows in the sand with their bodies when they want to rest, but this is nothing if one is familiar with such behaviour from cichlids.

The one unfortunate thing about the fish is its scarcity. I’ve only seen it twice at the shops, and I’ve seen SAE alerts on the Internet whenever someone has found them for sale. They also seem to be affected by the infamous Internet curse that plagues plecos, causing death to the discussed animal whenever one dares to mention its species by name (see Grant Gussie’s article), hence the abbreviation SAE.

So what else can I say about a fish that keeps my swordplants and stargrasses (Heteranthera zosterifolia) clean and intact, is not a fussy eater, gets along fine with my tetras and armored catfish, and amuses me with its antics? This fish really is worth its weight in gold.


Gussie, G. (1996). “Aquaria on the Internet: Part 4”. The Calquarium Vol. 39 No. 3

Horst, K & Kipper, H. (1986). The Optimum Aquarium. Aqua Documenta, Germany.

Sarakontu, L. & Frank, N. http://www.hut.fi/~lsarakon/algaeeater.txt ?