Catfish An Experience with Whiptail Catfish Of the Genus Rineloricaria
By Ian Fuller
The term Whiptail catfish points us to a group of fishes that are very unique in their physical make up. There are many genera that fall into the category commonly referred to as ‘Whiptails’ my experience with them has been limited to members of the genus Rineloricaria. There are around forty know species of this genus all of which have distinctive long thin tapering twig like body shapes that are covered over their entire lengths by hard interlocking bony plates known as scutes. Another striking feature of these fishes is their external mouthparts that are formed into suction like pads; some being more pronounced than others and may have lace like filaments on their trailing edges. The most difficult aspect with these fishes is their identification; many species have very similar body and fin markings.
When it comes to housing these fishes it is not too difficult as they are easily pleased, tank size is not that important so long as it is large enough for the fish not to be cramped. A 45cm x 25cm x 25cm tank would be adequate for a single pair and for the substrate; I would use fine gravel or smooth grained course sand with either internal or external power filtration. Filtration is to a certain degree a personal preference thing, but if an under gravel system is your preferred choice then I would recommend a slightly larger tank 60cm x 30cm x 30cm and larger sized gravel, the fine gravel or sand would soon become clogged and ineffective. A power head would be needed either fitted to the under gravel filter uplift tube or as a separate unit, this is to provide a good flow of water around the tank. Rineloricaria as well as other genera of whiptail catfish enjoy good water movement; in their natural habitats they are found in running fairly shallow running water. They are very strong swimmers but seam to prefer to maneuver them selves around using their pectoral and ventral fins.
Tank furnishings are again something that is a personal thing but these fish like to graze amongst leaf litter and on pieces of wood, I have a breeding trio of what I believe to be Rineloricaria hasemani Isbrücker & Nijssen, 1979 their tank is a 45 cm x 45cm x 45cm and is filtered by an internal power filter, the substrate is a fifteen millimeter layer of smooth course sand, the rest of the décor consists of three pieces of bog wood, two large clumps of Java Fern and two thirty five millimeter diameter terracotta closed of tubes. These tubes are normally used for large indoor plant displays where they are inserted to full depth into the soil, the pot and then filled with water, which then leaches slowly into the soil. Although not designed for the aquatic trade they make ideal breeding sites for Rineloricaria to spawn in, or for that matter any of the other smaller Ancistrine cave spawners.
Feeding Rineloricaria is not much of a problem because they will eat almost anything. I read in many publications that these fish are supposed to be vegetarian but I have found that all the plants that are in the tanks with all my six species Rineloricaria are perfectly safe, for that matter so is the algae that grows every where. I have tried the same experiment in all the tanks that I house these fish in, in each tank I have placed all at the same time, tablet, granulated and algae wafers. The fish are onto the tablet and granulated food almost straight away but with the algae food takes until the following morning before it disappears. I firmly believe that most if not all species of Rineloricaria are carrion and insectivorous, and the diet that I give my fish consists of frozen or fresh chopped muscle, frozen bloodworm, granulated catfish pellets, tablet, chopped earth worm and when available live blood worm.
Whenever I have tried feeding vegetable foods such as cucumber or couchette, these have been ignore and needed to be removed. The fact that two of the species are breeding tells me that their diet is pretty much to their liking.
Sexing these fish when freshly imported can be a bit of a problem unless the fish have arrived in really good condition, then usually the males can be distinguished by the fact that they have odontodes (Bristles) on the side of the head and on the upper surface of the pectoral fins. With some species the presents of odontodes is less evident and other methods of sexing need to be used. The first of these is the shape of the head when viewed from above; the head of the male is wider and less pointed than the female but she is wider and plumper in the body. The second area to look at is the pectoral and dorsal fin spine, which tend to be a little thicker in males. (Pic of shape and side for bristles) Some times it is really potluck when buying so-called pairs, especially if the fish are on the small side and immature, so when I cannot be one hundred percent sure I usually buy at least four, two fat and two slim, very scientific I know but it often works. Once the fish are settled and conditioned it will not be too difficult to tell the sexes apart.
In the tank with my trio of Rineloricaria hasemani I have two of the terracotta tubes and after about a week the male took up residence in one of them, he would stay in there all the time or at least until the lights went out and then he would come out and forage for food. The two females on the other hand were always out and about looking for food. Once a female had come into breeding condition she would join the male in the tube and the two of them would stay in there for several hours, or if she was not entirely happy only a few minutes. A day or so later she would join him again only this time when she came out the male could be seen lying on top of a group of largish, possibly three millimeter diameter greenish colored eggs. The male religiously sticks to his task of guarding the eggs for the following ten to twelve days, during which time as far as I could tell, because of not being able to observe any nighttime activity, he did not eat. When the young started to hatch they were all eaten by the male, so a month or so later they had spawned again, I waited until day ten when I could see that the eggs were very dark and nearing hatching, then removed the terracotta tube from the tank and gently expelled the male, who shot of and hid amongst the plants and bog wood, in fact I never saw him for about six days and then one day he appeared taking up residence in the other tube. The tube with the eggs in was placed in a shallow tank containing water from the main spawning tank; a sponge filter and an air stone to create fairly powerful water flow around the tube with maximum oxygen content. The following day all the fry had emerged from the eggs looking exactly like tiny miniatures of their parents. There were no signs of a yoke sack like I see with newly hatched Corydoras so I decided to put a little food in the tank, this was in the form of two broken up sinking tablets, by my return the next evening all the food was gone. Tablet and catfish pellets form the basis of their diet with a little chopped muscle. After their first month the fry have almost doubled in size and because of the amount of food they are getting through twenty five percent water changes are made every day. I have also introduced a dozen or so dried oak leaves; to help with water conditioning and to give the fry some cover, as there is no substrate in the tank their environment is quite bright which is unnatural for them. By the time they reach two months they will be ready to move into a larger growing on tank making the hatching tank ready for the next batch of fry, which will not be long in coming as the male is now sitting on another batch of light green eggs.