I’ve always felt there was something quite majestic about being able to watch a miniature coral reef together with the associated inhabitants, from the comfort of my lounge. I am of course referring to my reef aquarium.
After a time, you soon realise that fish establish a pecking order so far as dominance is concerned. Previously, I would always put my Banji Cardinal fish somewhere towards the lower end of the list. Generally speaking, they are a creature with a most peaceful temperament.
I was first alerted to some seemingly strange Banji behaviour, when my dear wife tactfully announced my fish were ‘bonking!’. Indeed, upon closer inspection I noted that my Banji’s were performing what can only be described as a crazy dance. It wasn’t so much a dance, it appeared as if each fish were convulsing – they looked like they were in distress.
As a paranoid aquarist, I’m aware that such signs can be an indication of water chemistry imbalance within a marine tank. A series of tests involving PH, Nitrite, Nitrate and Phosphate revealed all parameters were well within natural ocean boundaries.
That left only one possible alternative; my fish were on some form of illicit hallucinogenic drug. Seriously though, pregnancy in Banji Cardinals is something I had read about previously, but in the two years these particular fish had been in my tank, I have never experienced such thing.
Fast forward what I believe was a couple of days or so, the male’s jaw line looked to be more pronounced that usual. Furthermore, the area from his gill covers up to (and including) his mouth appeared to be bulging. It was the first time that the male opened his mouth that all became clear. I have no idea how he managed to fit so many eggs inside. Occasionally, he would open his mouth and move his jaw to rearrange the eggs that he was nursing.
Stand by your Man…
Throughout the period of the male incubating the precious eggs, his female would loyally guard him from any fish foolish enough to venture too close. Its important to remember, that all the time the male is holding the eggs, he is unable to eat. So long as the aquarium conditions are optimal, the male will hold the eggs for a period of roughly twenty five days.
Towards the end of the incubation period, the eggs hatch and small fry are finally released from the clutches of the father. Having read a few accounts online, I was aware that this phenomenon occurs during the hours of darkness.
Armed with a small flashlight and net, I sat up for a couple of evenings towards his ‘due date’. It was on the second evening that the beam from my light caught a flickering at the water surface. Sure enough, there were several small fish. The small fish were perfect miniatures of their fully grown parents. It really is quite remarkable, they taken on this appearance literally from the moment they hatch.
Having captured the babies (important, otherwise the other fish would have earnt themselves a free meal ticket), I placed them in a separate Biorb Fish Tank.
Feeding baby brine shrimp can be a challenge. I found that introducing freshly hatched brine shrimp (think sea monkey kits!) was the easiest way.
So here I am. The proud owner of five small Banji Carinals.