My question concerns the difference between semen (mani), pre-seminal fluid (madhy), and prostatic fluid (wady)?

Semen is a viscous fluid that exits in spurts with lust, followed by relaxation, and its smell is like pollen or dough. It necessitates ghusl (ritual bath). As for pre-seminal fluid (madhy), it is a viscous fluid, thinner than semen, that exits intermittently after arousal, and it necessitates washing the male organ and invalidates ablution. As for prostatic fluid (wady), it is a thick white fluid that often exits after urination, and its ruling is the same as that of urine.