You are only adding 1ml per 100 litres .
So weight gain is practically zero .
I've used it for over 12 months and it's amazing on the repeated visits to all my properties / customers .
But again I'm obviously affiliated to Vision . But I have never had any spotting issues since I've used Vision and my regular cleans are a doddle . Plus first cleans are no problem .
Used it hot today as well, again was very good .
i would simply just try it , we've had some great reviews .