Article © Bruce Brethauer, uploaded January 01, 2002.
I will try to clarify a few details for you but immediately we hit a stumbling block as to the identification of the species. It was sold to me as Farlowella acus; my fish bear a striking resemblance to photographs of that species in many books (I realize that there are a number of look-alike species) yet in speaking with people at planetcatfish.com, it appears the are in fact Farlowella vittata. This identification was only possible because I was able to take detailed photographs of the underside (ventral scutes) and 'nose' (rostrum) of both males and females to use in identification.
What I can tell you about (and indeed show you) are photographs of the eggs as well as a few images of the fry and parents. The spawning itself I can give some details on too. The aquarium is set up as a river tank (see this page for further details). It is a 55-gallon aquarium, with a Rio 3100 power head. The only filtration is the foam filters on the return portion of the 'river' manifold. I make frequent water changes, in which I siphon off and replace 10 gallons twice per week. I do not know the water chemistry, but suspect that it is slightly alkaline and of average hardness (I use aged tap water, which in this region tends to be a bit alkaline and contains lime deposits). Temperatures are slightly warmer than room temperature (due to the heating action of the power head and aquarium lights), so I would estimate that this is approximately 75°F at present, but in winter, may fall to about 68°F. The substrate is quartz gravel, with river rocks, mostly of quartz and granite, but also with limestone and sandstone. There is no bogwood in this tank at present, but I may add some in the near future. The plants in the tank include Cryptocoryne sp., Microsorium pteropus, Anubias coffeefolia, and Bolbitis heudelothii.
The other inhabitants of the tank include 7 Chinese butterfly loaches (probably Beaufortia levertti), 10 broken-band hill stream loaches (possibly Liniparhomaloptera disparis) an unidentified hill stream loach, related to Sinogastromyzon wui, a single Tiger whiptail catfish (a species of Rineloricaria), and two Royal Farlowella (Sturisoma aureum).
Until recently, I have fed the 'herbivores' on sinking pellets balanced for vegetarian fishes - the Broken band hill stream loaches are regularly given 'California black worms - but I have supplemented their diet with kale and collard greens. These are both a type of leaf cabbage and are much more nutritionally complete than lettuce or spinach. The fish devour it, consuming a large leaf overnight, leaving only the veins the next day. This diet seems to agree with them, despite the multiple spawning, I believe that my fish have increased in length and weight, and the females become gravid again about 4 to 6 weeks following spawning. I believe that two of my females are currently gravid, and will probably spawn in another two weeks or so. I do not know how long these fish can maintain this rapid spawning rate.
During a spawn I took the opportunity to have my water tested, and to take temperature readings when one of the multiple spawning occurred. The test revealed the following results:
pH is 7.1
GH is 0
Ammonia is 0
Nitrite is 0
Nitrate is 40
Temperature is 76°F (just under 25°C). It is possible that the relatively high level of Nitrate is due to an application of fertilizer that was made about 20 days ago. Since I am maintaining a river habitat, I regularly change the water. My aquarium is 55 gallons; about twice every week, I siphon off about 10 gallons and replace it with aged tap water.
The female lays very adhesive eggs, I my tank these were placed on the glass of the aquarium wall very close to one of the corners of the tank. One other interesting point of note from my observations; it appears that it is the female who initiates courtship. This is also supported by the fact that a single male will care for 3 clutches of eggs simultaneously, since he is more or less occupied with the task of caring for and protecting the eggs, he is not generally able to actively court other females. I suspect that the females preferentially mate with males that are already caring for a clutch of eggs, as I have two mature males in the tank, both of which have spawned with several females, but in every instance of multiple spawning, only one male was involved.
The image to the left illustrates a male with the eggs deposited by two females on 3 different nights. After the last of the eggs have hatched, I roughly estimate that I have approximately 150 fry in a separate aquarium. The odontodes on my male fish appear only on their rostrum.
One adult female appeared to be quite gravid, and looked as if she would be laying eggs soon. Should this happen I decided to produce a series of photographs that would illustrate the daily development of the embryos. Happily a spawn was not far away and you can see the photo series below. Click on any of these images to enlarge them and then use your browsers back button to return here, if you click on the enlarged image you will be taken to the image library.
|Day 1||Day 2||Day 3||Day 4||Day 5|
|Day 6||Day 7||Day 8||Day 9||Day 10 - Hatching!|
Above you can see the daily development within the eggs through until day 10 at which point hatching began. Complete hatching required an additional 3 or 4 days. There were many fry in this spawning; over 100 eggs, of which only one was infertile.
In this Cat-Elog page you well find more shots of the male and female together, although none with them in the process of egg laying or fertilization. Additionally there are my latest images of the Farlowella catfish and their developing eggs, both parent fish with some of the eggs (I caught the fish between waves of egg laying, as when I came home from work later in the day, more eggs had been deposited), some profile shots, studies of their scutes and finally odontodal growth on the males rostrum. These are useful in species identification (scutes) and telling the girls from the boys (odontodes). Below is an image of the newly hatched fry.
Once the fry have absorbed their yolk sacs, they must have a constant supply of food, otherwise, they will quickly starve. Lacinato Kale is preferred by far over all other foods, although older fry will also rasp at Collard Greens, Beet greens presumably Swiss Chard also, as this is just a variety of the common beet) and even carrots when these are provided. The mere presence of food is not sufficient; it must be soft enough for the fry to be able to eat from it. Garden fresh Kale needs a day or two of soaking, and carrots need as much as two weeks of soaking before they are soft enough for the fry to eat them. Even adult fishes have difficulty rasping a meal from garden fresh Kale. To hasten the process, I soak the Kale in water for about an hour, then transfer that to the freezer (it generally takes about half an hour for a leaf to freeze solid) and then anchor this in the aquarium for feeding. Freezing generally reduces the softening time to about one day, and probably preserves more of the nutrients than softening by par boiling.
Lacinato Kale and Collard Greens are easy crops in this climate, producing a continuous crop through the summer months, and well into autumn as well, so I am able to grow all of this vegetable necessary. One or two plants is more than sufficient for the needs of my fishes (with enough to spare for the gardener as well) I don't know how well these varieties will grow in your climate, but I am sure that there are a number of Kale varieties which are more suited to your region. I would avoid the ornamental varieties (with variegated leaves), as I believe that these have less nutritional value than the culinary varieties. I do not use lettuce and zucchini as a food, as these are low in nutritional value, and without supplementary foods, would insure a slow death by starvation.
I have tried other foods. Sinking pellets balanced for vegetarian fishes is accepted, but any food which contains higher percentages of animal proteins are ignored by both the fry and adult fishes, which is too bad, as these foods with their higher available caloric contents would probably speed the growth process of the fry.
In rearing the fry (or 'twiglets' - Ed) I cannot emphasize the importance of providing a constant supply of food. This food must be of the right consistency for the fry: even with pre freezing the Kale and Collard Greens, these usually need an additional day of soaking in the aquarium before they are sufficiently softened for the smaller mouths of the fry. For this reason, I add a second leaf long before the first one has been consumed to allow for the necessary softening period. The fry (particularly very young fry) appear to have virtually no reserves of fat, and are particularly vulnerable to starvation. Admittedly, the suggested food is fairly low in calories from fats and proteins, but even when given a selection of foods (including sinking pellets balanced for the diets of carnivorous fishes) the fry invariably feed upon the Collards and Kale, almost to the exclusion of all other foods. Water quality appears to be an important factor in the health of these fry as well, and I advise making regular changes of the aquarium water (I change about 20% of the water about twice per week, but may increase this to three times per week to see if this improves fry survival).
I am still learning the process of successfully rearing the fry, and must admit that I still have significant losses of fry in the early weeks. Growth rates have been slow, but perhaps with the proper diet, may be increased. A well-planted aquarium appears to be beneficial, providing the fry with cover and additional food in the form of both vegetation (usually only the dying and decaying leaves are consumed) and aufwuchs. Aufwuchs is a German word for the biocover of the aquarium decorations and panes. This thin layer of algae and the microorganisms contained therein are constantly grazed constantly by these limnivorous catfishes.
I should also mention that I have moved the fry of some broods into a separate aquarium, and have left fry of another brood in the community aquarium. Remarkably, in my community tank, none of the other fish appear to feed on the fry, and the process of separating the fry from community tank does not seem to significantly increase their rates.
Note on photographic equipment:
Although specialized, my gear is not particularly exceptional. I have a basic Nikon FM body, with a bellows attachment. I use one of several enlarging lenses that give me a range of magnifications from about 1/20 to 3x. I use a basic strobe which I bring as close as possible to the subject, and stop down the lens for best depth of field (most images were shot at F 11 or F16). If I had a low magnification microscope lens, I could get even better resolution. Aside from the bellows, most photographers would have the equivalent of my equipment (if not something better).
There is further information on this species on the Cat-eLog page.
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