only sensitive if there are sharp objects in the tank. Its like an egg yolk on water... thats the best wat to describe it. My pond has only smooth plastic surfaces. They do have a little trouble eating though.
Anne, they had trouble eating because they seem to not be able to find food very well. Their eye bubbles almost cover their eyes. Its actually a cruel disign for a for a fish when you really think about it
Tahnks for the compliments everyone. I am enjoying them