A:Hi Rawlins... Well it means that if you talk loud to these bettas they burst into tears LOL. They are very sensitive. Require someone with a soft voice, a way with words and can only be kept in a room with pastel colored wallpaper. LOL.
OK, I'm pulling your leg here ;). You asked a good question because it is going to allow me to go on a bit of a tangent (my favorite pass time), but I assure you a very useful tangent that will eventually answer your question as well (two birds with a stone) (or should I say two fish with a net??).
As you all know, there are many betta strains out there, offering a wide variety of colors and color combinations. A good example would be seen on my catalogue page, by just scrolling down and up the left window. You can see all sorts of betta colors right there.
Now, these colors are created by manipulating genes that the bettas carry, in such a way that they interact with each other causing an alteration of the original color, hence creating new ones. For example, yellow bettas were created by taking red bettas and manipulating the genes to cause the red pigment to fail to develop, leaving a yellow color in its place.
Now let look at another aspect of genetics. All of you know that some genes are dominant, while other recessive. The dominant genes will express themselves when mixed with other genes, while the recessive ones (more shy LOL) will tend to hide in the background and not show. For example if you breed a blue betta (a pretty dominant type color) to just about anything, you will get the blue to show up in the fry. Say you breed a blue (dominant) to a opaque white (recessive). All the fry you get will be blue. Not a ONE will be opaque white. Why? cause the opaque white color is recessive (to simplify things) so it "hides". It is really there, but you cannot see it. Later on when you breed two fry that both carry the recessive genes, they will recombine together to express themselves again (think of it this way: safety in numbers, when there are two of them they feel more safe and less shy and come out of hiding and show themselves LOL). THEN you will get white bettas.
Once we understand the above concept then we can easily grasp the next wave of new info I will now attempt to cram into your heads. Hehehehehe...
When one works on a color type that is recessive (for example: Melano blacks, White opaques, Oranges), one will have to breed fish with same genes in order to get the color to "come out of hiding". This limits the outcrossing (crossing to a different strain with fresh blood) possibilities. This is especially true when one works with a light colored betta type (for ex: White opaques), because with these bettas any color impurity will show a lot (sort of like when you wear a white shirt and try to eat spaghetti smothered with tomato sauce - you get the messy picture). Now if you wear a red shirt, you are ok, a black one, also (sort of, but I am sure your wife thinks otherwise LOL).
So now back to bettas (all this talk about pasta made me hungry so let's wrap this up so I can zoom down the hall to the cafeteria and have - at long last- my lunch break darn it!! LOL). Recessive colors will always be more inbred than the more dominant ones. When you inbreed, you weaken. It is however a very necessary evil, (one we cannot avoid). So in closing, some strains are more "sensitive" than others because they are recessive strains and more inbred. These bettas will tend to get sick faster, live a bit less long and provide more of a challenge to the breeder. Hence I usually do not recommend them for total beginners. This is not to say that these bettas are not healthy or hard to breed etc... As a matter of fact my Holy Grail opaque line always seems to yield great breeders (very willing to perform). But 'sentivite' strains will be less forgiving of your mistakes. So you have to know what you are doing, because if you don't, they will let you know right away LOL. So it is important that a betta hobbyist understand that bettas are like ski slopes. Faithyoda says: Better not the black diamond trail take when you fresh out of the bunny slopes are or you hurting will.
OK, now let's go pig out! :))
PS: I just came back from the cafeteria, and wouldn't you know? Today's special is: breast of chicken smothered in tomato sauce. (I'm not even kidding). Oh, and I am wearing light colored silver crushed velvet. Should I fast?. NOT!