Nannostomus Eques - Brown-Tailed Pencilfish By Rene Jez
In the years when I was in Europe, a long time ago, I used to maintain a school of this funny looking fish which was always present in my community tank. Because the import laws of exotic fish into our country had a zero priority and was considered only a luxury, these rare and somewhat difficult fish to breed were always asked for by the hobby shops. The sale helped to cover the very expensive electricity cost.
I had always a sort of an affection for this fish and occasionally bought a few fish with the intention to breed them. Some Sydney shops had rather poor stock and the results, considering the investment, would be very poor. A year ago, I had discovered a tank full of these fish in a Canberra shop, which were extremely small but promised more in the long term because the fish can be conditioned and brought into maturity with some care. The cost was a fraction of the Sydney price.
My first purchase was 15 fish and as a matter of disease prevention have I accommodated them in a small tank, to save an additional heater. Feeling they should be fed well from the beginning, I have added a good number of Cyclops. As usual, Murphy’s Law proved correct, little fish get irritated by the number of cyclops in the tank and during the night I had lost half of them. Only the few who jumped out of the small tank into the big tank were saved. The next day I went, for the second time, to buy some replacements and the immediate investment didn't look so attractive.
This or similar problems happens to me frequently,I know all about it, but never learnt the lesson. After that, all fish survived and developed into very nice specimens. At least the start was made.
The fish originate from the basin of the middle reaches of the Amazon and Rio Negro rivers. In nature it keeps close to the banks near water plants and decaying wood. It grows to about 60mm long. In captivity it prospers best when kept by itself but I have found no problems when kept it with other tetras.'
They always swim at an angle of about 45 degrees, the water should be low in hardness and the pH kept between 6.5 and 7.5. The male is slimmer than the female when mature and its pelvic fins have white margins and white tips. The body is mostly black with a silvery underside.
For breeding, a small tank of 7-10 litres, clear soft water and a pH reading of 6.0-6.5. Place in the tank a broad leaf plant like Cryptocoryne or an Amazon Sword, wash it and place it with the bare roots held by glass strip on the tank floor. The fish spawn on the underside of the leaves and during the spawning act the female ejects 1-2 eggs and sticks them to this surface. Spawning yields usually 30-40 fry but higher numbers under ideal conditions are possible.
The water temperature range for spawning should be between 24-28 degrees celsius, fry hatch within 24-36 hours and in 5-6 days start to swim. They are very unusual by swimming nearly vertical and being black they are very visible. The advantage of the try feeding is they collect micro-worms from the tanks bottom which solves the problem of lost food once fallen down. They require very small food for at least a week to ten days then micro-worms can start to supplement the diet with small Cyclops or Daphnia.
In a month, they reach 7-10mm in length and appear quite hardy as to the quality of water and to pH fluctuations. It takes 3-4 months to bring them up to the size not to be swallowed by other tetras. This exotic looking, peaceful fish is worth keeping in our tanks and gives a lot of satisfaction when one can maintain a school of this bizarre fish.