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A fish I hadn't heard of and certainly never seen! Late in the year 2005, I was fortunate enough to see a group of these in a friend's tank. He had been given a pair, many years ago, from a fishkeeper who had raised them in good numbers as part of his breeding programme. On attempting to find information about them, I began to realise why I wasn't aware of this species! Apparently quite a rare fish which is close to extinction, if not already extinct (due to the usual human "interference") in its native country. Location It was found in Lake Lindu in Central Sulawesi, but in the early 50's (?) some predatory fish, believed to be Tilapia and Channa Striata, were introduced into the lake. This had the obvious disastrous effect on these native fish. Over the following years the threat to these fish continued and was further increased due to deforestation and pollution. Background They are a member of the Adrianichthyidae, the Ricefish family, but are sometimes referred to as "Sarasins Minnow" or Sarasin's Duckbill Fish. They can be kept at a temperature of between 24c and 29c, with the PH around neutral. I believe they can reach almost 10 cms in length. Sexing the fish The female is a pale Olive green colour and has a hollow behind her vent, (the egg area), with elongated pelvic fins which help to keep her streamlined.  During the spawning sequence the female will gradually amass her eggs which resemble a bunch of grapes. These are attached to her pelvic fin area by filaments. (Hence the Ricefish connection). She will then carry them for 15 to 20 days until they hatch whilst still attached to the fins. (She does not drape them onto the plants as Ricefish do).  The male is a similar colour but his anal and dorsal fins are much bigger. Also the anal fin has a ragged and uneven appearance. However during his courtship ritual and spawning, his body colour goes much darker and the anal and dorsal fins become almost black.  In May, 2006 I was fortunate enough to be given a small group of fish from a fellow fishkeeper. All the fish were a little over 5cms long. I was more than surprised to find I had the bonus of a cluster of eggs hanging from one females vent.  My first task was to provide a place of safety for the female and her eggs. As I didn't know when these eggs had first appeared I put her straight into my "maternity ward";- I put a divider at one end of the 36" tank. I made it only 8cms wide and crammed in a lot of Java Fern and some Java Moss, thus creating a birthing area. The rest of the group I put in the remaining larger part of the tank. To settle them in I dropped in some daphnia from my pond which usually goes down well and then I would try them on other foods. All the fish had settled in well and ( big eyes don't miss much!), soon picked up food, even any which had settled on the gravel. They ate frozen Bloodworm and Black Mosquito larva as well as Flake. Also, with their almost Pike like shape and quite large mouth, they were very quick to grab Daphnia. |
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On later births I left her in the main tank until around the 15th day and then eased open a side of the divider and coaxed her to that end and through the gap. This works quite well and avoids the clumsiness and stress of netting. |
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At this stage there seemed to be around 8-10 eggs. The female was constantly doing a "body shimmy" as if to shake the eggs and cause some circulation of water round them. Is this her "technique" to create some extra water movement between the eggs to try and ensure that they don't fungus? Egg development By the 4th day however one of the eggs was a solid white colour;- infertile? In a situation like this, not a lot I could do except observe and hope! Perhaps some feat of nature, but a few days later the white egg had gone and the black specks inside the remaining eggs were getting larger. However, 3 days later and another white egg! By now she had carried the eggs for at least 15 days and hopefully they would soon hatch. By now the egg cluster were also hanging much lower and swinging more when she did her "shimmy". At this stage there was also a clear yellow glint in the eggs (see photo),which were certainly the big eyes of the fry.  The day after this photo and the eggs have hatched. I carefully removed some of the Java Fern until I could net the female and put her temporarily in a half toffee jar. I then removed all the plants and netted and glassed 7 fry. These I put in a small 16" aquarium. I then put the female back in the now vacant part, to give her a break for a few days, before returning her to the group. Courtship.... Within one week of returning her, one male was much more attentive and during his displaying became a very dark colour, almost black. He would tup the female around the vent and follow this up by darting quickly up to her and away. There was however a unique part to his display and one which I had not seen before. As he approached, he went into a strange headstand position in front of her, going almost vertical and hovering there. This more dominant male who was paying her all the attention, also turned very dark when driving off his competition.  The fry... They were a slim, pale fish with a bold eye (as expected) and about 4 mm in size. Early growth was hardly discernible but by the time they were just over 3 weeks old, their fins had developed and they had reached 7-8 mms. |
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At 3 weeks old I transferred them to a 24" planted tank with just Corys for company. I was giving regular batches of Microworm, little and often, over this period and hoping they were also weening themselves onto some fine powdered flake which was drifting round for the Cory fry. At 1 month old they were still on live foods, feeding on microworm and also snatching the tiniest of daphnia. At this stage they were a pale silver grey colour. My next drop was a disappointment as I only found 1 fry in the plants. At 5 weeks old I deliberately reduced the "easy" live food of microworm and this had the desired effect. Instead of swimming mainly middle and upper water, they were now actually looking for food on the bogwood, on the broad leafed plants and in the gravel;- apart from any micro-organisms, they were certainly having a pick at flake "dust". My third female had by now a cluster of eggs. Again there seemed to be perhaps 7 or so eggs hanging from her vent area. As yet not sure of the maximum number to hope for but I managed to rescue 5 fry, which seemed a reasonable return. This meant I now had a total of 13 fry (from three drops), all at various stages of growth. At 3 months old the juveniles were approx 2.5 cms in size. They were still "picky" eaters with flake (often ignoring it or a grab, then spit out!) but were now taking very small bits of frozen bloodworm. Despite what I thought was a fairly large mouth, I was quite surprised how they couldn't take slightly larger daphnia! At this age their growth seemed to "plateau" and for the next month, there was no change in size at all. With tank space always at a premium, my dilemma at this time was, whether they were big enough to put back in with the adults? A different birth pattern..... A surprising incident took place with my fourth drop of fry. On the previous three births I had seen that the eggs had gone, quickly removed the female and then searched the plants and removed any fry. This time, when I looked in first thing in the morning, the eggs were hanging very low and seemingly ready for birth. One hour later I saw that all the eggs had gone;- I removed the female, then took all the plants out carefully and sadly found not one single fry! I couldn't believe that none had survived in the plant cover. However the following morning I got a real surprise! I saw 3 fry swimming near the surface of the now plantless "maternity" section. I started to net and glass them and caught 10 fry, a new record number! Obviously she had done some extra vigorous "shimmies", causing the eggs to drop into the gravel where they had hatched 24 hours later. With this birth I did notice a different body shape;- previously the fry were a slim torpedo shape, this time the fry had much more of a bulbous "yolk sac" tummy but they were all healthy looking. The yolk sac had gone after 2 days and all 10 fish grew on well with no losses. When to return young fish to the main tank ?. . . When the juvenile fish were approx 3cms+, I decided to put them in the main tank with the adults. The adults reacted by darting at the newcomers and driving them away from "their" end of the tank where the filter was. Apart from that, there was no attempt to chase them with the intention of grabbing one. The following week I put in 4 more young fish but slightly smaller as a little "test" and again they were fine. Update;- January, 2007. Eight months later and I had a total of 25 juvenile sarasinorum, with some in the main tank and the remaining developing youngsters in a 24" tank. Update;- June, 2007. A couple of "milestones" during this month, the early part of which I put in all the remainder (15) of my juvenile fish from the smaller tank, some as small as 1 cm. Pleasingly, no fish were lost. Firstly, some fry have hatched in the 36" tank which isn't as yet overly densely planted. After 1 week, three survivors are swimming around quite confidently but sadly disappeared soon after. Secondly, my very first group of "fry" are now one year old and one of these females is carrying her first cluster of eggs. I wasn't sure at what age they could have fry. Summary;- Jan 2008. All the fish are doing well in a colony situation. They have grown on well and many females are often carrying eggs at the same time. I now have half the water surface covered with a dense layer of Indian Fern where I often spot fry moving around. As I have enough adults, I leave them in the tank but sad to report, as yet none have survived to a sufficiently sized juvenile. They are a really interesting fish to keep, particularly due to their method of giving birth. Also, during this time I had only lost 2 fish which simply confirms that, although they are a rare fish and not seen too often in any aquatic outlets, they are hardy and not at all difficult to keep and breed. Copyright;- Text and photos; Ivor Hilton. |
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