My boy is also 6 months old and having diarrhoea since Mon. He is still active and not fussy. Poo-ed 5 to 6 times a day. Brought him to a GP and was given med and probiotic. GP also advised to avoid normal FM and feed him with Isomail for the time being as it is soy-based, and tentatively stop BF until his stool is not so watery. BF babies' poo is generally more wet those drinking FM. However, this is subjective as most ppl will still BF. So far his poo yesterday was so watery. I'm still monitoring to see if he's better with these. If at any point, you feel unsure, just bring to see doctor. Better be safe than sorry...