Fish in Timeout

This weekend we had to discipline a fish.

One of our platys is obscenely pregnant. A second now seems also to be in the family way. We had been debating getting an isolation chamber—baby fish are tasty morsels, and though we don’t object to the bulk being eaten, would like to observe platy development from the 1 millimeter stage on.

The debate ended when a male platy—we assume, he doesn’t look pregnant—started chasing the vulgarly pregnant one. So we bought a mesh “baby saver” box that clips to the side of the tank.

Once the enormous one was isolated, the mean male platy started chasing the less egregiously pregnant one. The other male platy (again assuming gender by lack of pregnancy), wedged himself between the mesh and the tank glass, drooped like a u-lock, and refused to swim. If I were to attribute emotions to fish (see Blog 1), I would say he was the Byron of fish, composing drippy ballads about his separated love.

We watched this for a bit. The mean platy got meaner; the lovelorn platy moped. Our littlest danio hung motionless under the isolation chamber, refusing to join the boisterous circling of his peers. The final straw came the next morning: our frog had wedged himself between the mesh chamber and the tank. I thought he had squished himself unintentionally; however, once released, he instantly wedged himself again. After repeating the release and re-wedge scenario a few times, I became convinced that this position was his independent choice.

Given all this, we decided to remove the isolation chamber. Everyone seemed happier. Mr. Lovelorn perked up. Littlest Danio rejoined his peers.

But then Mr. Mean starting chasing and biting both pregnant platys. Afraid that they would give birth prematurely from pure stress, we googled. Apparently male platys often pursue their desired mates to death (from exhaustion), or at least bite off their fins. Counterproductive?

We decided to punish Mr. Mean by sending him to the isolation chamber—seemed fair since he was the problem. The other fish didn’t seem to mind the isolation chamber the second time around, and the platys clearly were delighted at the removal of Mr. Mean.

The funniest thing is that it worked as behavior modification. After two days in the isolation chamber, Mr. Mean is now a reformed character. He has only once given chase—and that half-heartedly—to the lady platys.

Not sure how long this remarkable turnaround will last. But if Mr. Mean relapses, we can always send him to timeout again.