A few months back, I expressed my disappointment in regards to the small number of offspring produced by my wild-caught Betta livida pair. With tougher import laws in effect, and very few if any, hobbyists in Australia working with this species, there was the real risk that I could lose this species from my fish room. Therefore, spurred into action, I set about separating the pair out for a second breeding attempt.
This time it seemed luck was on my side, with my pair producing a much greater number of offspring than they had done previously. All up, I was left with between thirty to forty juveniles to work with. Because not all males display the iridescent green blotch (as shown on the fish in the above photo), it can be difficult to distinguish between females and young males until the fins are at a later stage of development. So while there are some very obvious males, there are more than a few fish of ambiguous sex, and at this point, it's very much a waiting game.
For those curious about the breeding tank set-up, I used a 30x30x30cm cube. While this was smaller than I would have preferred (mature Betta livida are quite large), they spawned much more frequently in the cube than in their previous tank. As in all my tanks, the substrate used is ADA Malaya. Filtration is a sponge filter turned down to a slow trickle, and the heater is set at around 26 degrees Celsius. Unfortunately, due to a lack of testing equipment, I can't provide exact parameters, but Melbourne tap water has a very low carbonate hardness, and from what I've read, quite a low level of TDS.
One difference with this tank, and other tanks in my fish room, is that the water was almost black with tannins, which had leeched out from the two hollow logs added as potential nesting sites. While my Betta livida pair seemed more interested in hiding in the logs than spawning in them, I'd never seen my pair as vibrantly coloured as they were in this coffee coloured water. Unfortunately over time, the effect has dissipated, and now the water is closer in colour to weak tea.
Obviously, the main disadvantage to a smaller tank, is that the juveniles are very quickly outgrowing it. So while I personally dread moving young fish, a move to a larger grow-out tank is definitely in the immediate future for this group.
Hailing from Melbourne, Australia, I currently keep and breed a number of species from the coccina complex.