Img 1
Img 2
Fluid pipes produse strange thing when placed like Image 1
Reproduction

1. Place pipes like on image
   
2. Place tank like on image
   
3. Conect one from pipes to tank, And set pipe to extract mode
   
4. Add any fluid to tank
5. Replace tank to pipe
   
6. Conect empty pipe to pipe whin fluid, Not fluid pipe to empty pipe