Bob Mehen advises one of our readers on whether their tank is suitable for hatchets...
Q) I’d like to keep a group of hatchets to add some life to the top of my 150 l planted community set-up. The tank is covered, so jumping won’t be an issue but I’m wondering what to feed them, as I presume they only take food from the surface. Also, how many would I need and is any one species easier than the others? The tank temperature is 25°C, pH 7.4 and the water quality is excellent. The tank has been set up since August last year.
MARK NICHOLLS VIA EMAIL
A) Bob says: Your tank sounds ideal for hatchets and they make fascinating aquarium subjects. There are a couple of possible choices that fit your tank size-wise. The most commonly seen is the hatchetfish, Carnegiella strigata. They’re lovely little fish with, as their common name suggests, attractive brown marbling over a silvery body, and a gold stripe running from nose to tail. With a maximum length of just over 3cm, a group of 10 would fit nicely into your tank.
Also seen from time to time is the Pygmy hatchetfish, Carnegiella myersi, which is a beautiful little silvery coloured fish with a black stripe along its lateral line and a maximum size of 2.5cm. There are several species of hatchet sold under the ‘silver’ banner, but you need to be careful with these — some of them are quite large fish when fully grown, so may be unsuitable for your tank.
Once settled they usually adapt well to dried floating foods, such as flake or granules, but you can supplement their diet with the occasional treat in the form of live fruit-flies. Wingless versions of these are available from many reptile stockists and help replicate the hatchets’ natural diet and hunting behaviour.