short vid i took of my betta babies. they are eating by this point. what i found interesting is that they never stop moving their fins, they look like little hummingbirds or something. anyway, because of this, i am going to go ahead and assume that they need a large quantity of fatty foods in order to have enough energy to grow on top of the continuous beating of their fins.
this may be why betta mahachai babies grow so slowly. i have never looked at regular betta babies under a microscope, so i have no idea if they share the same behavior.
in the video, it looks like the tips of the fishes fins are blurry, like i didnt get them focused in. its actually them vibrating. the fins are flat on top, but seem to stretch down toward the belly gradually, instead of suddenly, like the top half of the fin does. when the betta vibrates the fin, it sends ripples that go straight down to the bottom of the fin, which is connected closer to the belly. this sends water going straight down. i did a couple experiments in light exposure and found that the fin vibrations is how the fish stabilize themselves from left to right. that is, its how they keep from flipping over sideways. neat way of doing it, i have never seen quite the same thing in the fry of any other fish.