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I've had Beckford's Pencil Fishes for close on a year now, and I thought it would be appropriate to pass on some notes regarding these fishes to prospective keepers, not least because some of the observations I have to make are not only interesting, but at variance with some of the comments one tends to see in textbooks.

First of all, one aspect of this species that the textbooks are correct about is this: among the assorted Pencil Fish species, Beckford's Pencil Fish (Nanostomus beckfordi) is definitely the hardiest. While some Pencil Fish species can be more than a little finicky with respect to water chemistry, aquarium furnishings or companions, Beckford's Pencil Fish is a tough little character. Given that this is an Amazonian fish that can also be found in the blackwaters of the Rio Negro, one might expect it to demand soft, slightly acidic water, but captive bred stock in particular seems to be capable of living in any water that is capable of maintaining fish life across a broad pH and hardness spectrum, although extremes are obviously to be avoided. Anything between a pH of 6.0 and 7.6 is acceptable, with a preference in the middle of that range.

Now to some of the comments that need to be re-evaluated. First of all, while it is true that Pencil Fishes have small mouths in relation to body size, and beckfordi is typical in this respect, my specimens have never encountered any difficulty dealing with food particles that, according to the books, should be impossible for them to eat. Flakes are cleverly nibbled from the outside inwards during descent through the water, while live foods are quite simply engulfed. Not only will even juveniles devour live Daphnia with ease, they will attack live Bloodworm with relish, and surprise the aquarist with the speed and efficiency with which they can devour them. Indeed, I have even seen one of my male Pencil Fishes steal a live Bloodworm right from the mouth of one of my Panda Corys, leading to the behaviour change upon their part that I have documented frequently on this Board! Make no mistake, these fishes are efficient feeders, and although they appreciate having flake foods ground to a small size to make their task easier, they compete very effectively with my Lemon Tetras for the available flakes once the hood is raised, and it is unusual for them to be 'caught on the hop' at feeding time. While I would exercise caution with respect to food size in the case of fry, once adult colouration appears, these little fishes prove to be enthusiastic pursuers of all things edible. I've seen them ravenously dismantle fully grown adult Brine Shrimp without any trouble, and relish doing so.

Next, shoaling behaviour. Pencil Fishes do shoal, yes, I've seen mine shoaling frequently, but the books do not mention a plethora of other behaviours associated with Beckford's Pencil Fishes. "Jousting" between males (which I have photographed in action) is a classic example - nowhere in the books will this behaviour be mentioned, yet my males will perform this action regularly. After a moment's circling each other, two males will suddenly draw alongside each other, facing the same direction, and suddenly begin pushing against each other with a sinuous motion, while simultaneously reversing and adopting a head-down position, sometimes almost becoming vertically oriented. Once thus engaged in "jousting", they will continue for anything up to 15 minutes at a stretch in this activity, seemingly oblivious to all around them, to the extent that in my aquarium, even the bustling activities of spawning Panda Cory males fails to separate them. I have even seen excited male Panda Corys collide head-on with jousting male Pencil Fishes, only for the Pencil Fishes to shrug off the collision and resume jousting. Body colour darkens noticeably during this activity, and those parts of the body that are red become more intense, which makes them not only behaviourally interesting to watch during a jousting session, but colourful too.

Next, peacefulness. Beckford's Pencil Fishes have their placid moments. And during these, behave much like any other small "community aquarium" Characin. But, they have a dark side. Sometimes, literally as if a switch has been thrown inside their heads, males can begin behaving for all the world like Mbuna. And if that comment makes the eyebrows raise, read on and I shall explain. Male Beckford's Pencil Fish exhibit what could be best described as 'part time territoriality', in a manner akin to Silver Tip Tetras (and for that matter my alpha male Lemon Tetras), whereupon they pick a landmark in the aquarium (usually a tall plant thicket) and use that as a station for displaying. This display does not seem, for one moment, to be for the benefit of the females, indeed, male Beckford's Pencils frequently behave as if they inhabit their own chauvinist universe, in which the females more or less do not exist, concentrating instead on macho posturing (of which the jousting cited above is a typical example). Furthermore, once the testosterone is flowing, male Beckford's Pencils can engage in combat that bears more relation to Cichlid mayhem than anything from the Characin world, and the nearest parallel I can find here is the activities of male Mbuna toward each other. Once they have adopted their part-time territories, they see off interlopers with a vigour that has to be seen to be believed - one day, if I can borrow a video camera, I'll film them in the act and surprise everyone with just how much like Mbuna these little fishes can be!

Not only are male Beckford's Pencils capable of behaving like ruffians toward each other, but at times, they can be vicious toward any females that stray into the macho wrestling pack. "Wife beating" is a phenomenon I've mentioned in past posts covering this species, and in some cases, it can actually result in dead females. I have one male Beckford's Pencil Fish in particular that is a complete sociopath at times, showing not the slightest hint of gentlemanly restraint in the presence of the ladies, and the other males, while less extreme, are similarly given to slapping their womenfolk about. Perhaps I have a particularly recidivist bunch of criminals in my aquarium, but in my experience, these fishes need watching carefully because they are capable of lamentable violence against the females. Even if the females heavily outnumber the males in a shoal, they may find themselves mercilessly harassed if sufficient retreats are not available, and even this may not lessen the male's fury (for whatever weird reason has formed inside his own head) once he begins his tirade.

Therefore, I would now advise, on the basis of my experience, choosing the individuals in a shoal of Beckford's Pencils with care. First, the more, the merrier - spread that male bad temper across as large a population as possible. While most people think of six Characins as a 'shoal' for community aquarium purposes, I would, if space allows, suggest a minimum of twelve. Furthermore, I would either keep just the one male among a large harem of females, or opt for a big bachelor herd (much as is sometimes recommended with Rift Lake Cichlids), so that they can work off their testosterone among each other without leaving a trail of battered wives in their wake. When planning an aquarium for these fishes, bear in mind that they can see each other across quite a stretch of water, so plan ahead. These fishes will use tall plant thickets preferentially as their 'part time territories', or plants growing atop bogwood such as my Java Ferns and Java Moss, so try and place these in such a manner as to break up 'lines of sight' as much as possible. I've recently found that allowing strands of Hornwort to float, partially weighted so that some stems dangle down into the water, seems to have a calming effect upon these fishes, which probably means that their natural habitat contains vegetation of a similar nature. I've never seen Amazon Frogbit in my life, but if that plant adopts the habit of my partially weighted Hornwort, and provides cover for Beckford's Pencils in the wild, then this may explain my latest observation. Perhaps if someone could point me at a photograph of this plant in situ in an aquarium, then this would aid my speculations in this vein. Oh, and a taxonomic name for Amazon Frogbit would be nice too

Make no mistake, Beckford's Pencils are lovely fishes, with vibrant colours, and the intense iridescent azure-blue pelvic fin tips of the male in particular rival the blue stripe of my Cardinal Tetras for brilliance. They are also every bit as tough and hardy as the books claim them to be, but the stereotype of 'small, peaceful Characin' grinds to a halt there. At times, these are Characins that think they're Mbuna, and exhibit a feistiness more characteristic of big Cichlids than small Tetras, which just goes to show that even the big names in the aquarium book world can get it wrong. By all means, take them on, as they make a sparkling display in the right setting (a shoal of 24 in a shallow-draught 6 foot long aquarium would make a dazzling sight, especially if accompanied by Cardinals), but be prepared for behaviour that does not conform to the 'small, peaceful Characin' stereotype even in such a spacious setting. Yet despite all of this, I would still recommend them as a "First Pencil Fish" precisely because they are so tough, as well as being a lot more attractive than many of the books again give them credit for (did the author actually see the species in that case before describing it as "a less colourful brown Pencil Fish"? Brown? Check out my photos - at most 10% of the body along the back near the dorsal is brown!). Don't be afraid to give them a try, as they are rewarding fishes to keep, but do so with your eyes well and truly open, and be prepared for some very un-Characinlike behaviour once they're settled in!

Enjoy!

Panda Catfish fan and keeper/breeder since Christmas 2002