Ok. I spent my whole afternoon preparing a new tank for them, which has a division (I used this tank before to house 2 bettas), So after all the hard work, I went to brew myself a cup of tea, and when I came back to admire the result, the 2 males were already at the other side!

Don't ask me how they did it. The dominant male was able to get back to the other side, but the other had not. So, this division is no good I thought it was a good idea as it would ensure the same water characteristics and would make it easier to put them together for breeding afterwards. Now I will see what I can do with regard to this division. It is made out of acrylic and has holes in it. For a start I am thinking of covering it with musquito mesh.

For the 'lid' I am using a piece of cloth to which I have sewn an elastic band. I thought this might work well, as it ensures that it is tight and at the same time allows air in. I will try to take pictures of it later.