How do I breed my half­beaks?

Practical Fishkeeping (UK) - - Answer -

I've had six Sil­ver half­beaks – not sure of the ac­tual species – in my 120x38x38cm tank for about five months and they are now a good size. What size of tank would I need to move them to for breed­ing? Do they need con­di­tion­ing? What is the best decor and how do I rear the young­sters? Do I need to re­move the adults? JO B, EMAIL

NEALE SAYS: Breed­ing half­beaks is tricky, but def­i­nitely not im­pos­si­ble.

Let’s start with the ba­sics. Yes, the adults do seem to need a good diet to en­sure their fer­til­ity, with at least some small live foods in­cluded. Win­g­less fruit flies are prob­a­bly the best thing you can of­fer them, and these are avail­able mail or­der and from pet shops cater­ing to the needs of small rep­tiles and am­phib­ians. Oth­er­wise, a var­ied diet of frozen foods such as blood­worms and brine shrimp should be pro­vided, along­side good qual­ity flake and pel­lets.

So far as their aquar­ium goes, plenty of open space at the sur­face and float­ing plants will be wel­comed. Oth­er­wise, the decor is up to you. In my ex­pe­ri­ence, half­beaks will swim at dif­fer­ent lev­els of the tank, even feed­ing from the bot­tom at times, but they do pre­fer to stay close to the sur­face. Some­times they’ll hang about near the out­flow from the fil­ter, but at other times they’ll find ar­eas with lit­tle wa­ter cur­rent, so it’s a good idea to pro­vide a mix of en­vi­ron­ments within their aquar­ium. Ju­ve­niles in par­tic­u­lar seem to like to lurk among float­ing plants in those parts of the tank with very lit­tle cur­rent. As­sum­ing your Sil­ver half­beaks are a

Der­mogenys species, then your present aquar­ium should be fine. Any­thing around the 100 l/22 gal mark should be fine for a small group of these lit­tle half­beaks, and the larger species, among them the pop­u­lar Celebes half­beaks No­morham­phus

liemi liemi, are bet­ter suited to sys­tems up­wards of 150 l/33 gal.

Sex­ing shouldn’t be an is­sue – the males are smaller than the fe­males, of­ten more colour­ful and, like gup­pies, have a mod­i­fied anal fin used to di­rect pack­ets of sperm into the fe­males while mat­ing. Also like gup­pies, the males are con­tin­u­ally spar­ring with each other or try­ing to mate with the fe­males. But un­like gup­pies, the fe­males aren’t con­stantly preg­nant – or, if they are, don’t seem to con­sis­tently de­liver broods of healthy fry. It’s been ob­served that older fe­males are less fer­tile than younger fe­males, which may have some­thing to do with their diet, but it’s hard to be sure. One prob­lem is a ten­dency to­wards mis­car­riages, pos­si­bly caused by stress. While that can hap­pen with gup­pies and mol­lies, it’s much less com­mon, so we of­ten leave males and fe­males to­gether. But when it comes to half­beaks, you do need to sep­a­rate the sexes if pos­si­ble, so move the males, rather than the preg­nant fe­males. Oddly enough, half­beaks are not es­pe­cially preda­tory to­wards their fry. Given the right con­di­tions, half­beaks will breed with­out too much trou­ble, al­though brood sizes aren’t com­pa­ra­ble to those of other live­bear­ers. Of course, pro­vid­ing the right con­di­tions can be a chal­lenge be­cause half­beaks aren’t al­ways prop­erly iden­ti­fied, which makes op­ti­mis­ing wa­ter chem­istry dif­fi­cult. If all else fails, neu­tral, mod­er­ately soft to slightly hard wa­ter is a good start­ing point for the big­ger No­morham­phus species, while the smaller Der­mogenys pre­fer slightly ba­sic, mod­er­ately hard wa­ter. Some peo­ple add a lit­tle salt (2-3g per litre) to tanks with Der­mogenys, which may help if your spec­i­mens are strug­gling.

Newspapers in English

Newspapers from UK

© PressReader. All rights reserved.