Don't know if I've just been having a bad run or if there was a nerf, but the pure water pools up on the Elemental Plateu have been only giving me two successful catches each before poofing lately - previously I could catch the usual 4-6 items from them before they poofed?
I have got an impression, that usually freshly respawned pure waters include less catches (two to be exact) than the pools that stay some time in the lake. However, this is my impression only and I did not do any research in this matter.