Some funny smell from 225 (coolant)

ive had some cars that couldnt keep full, let it be at a quart or 2 low and it stay right there for years but fill it to the rim it lose a quart or 2 every few days!
Sounds strange but I will check out if it is the same case here. The funny thing is, my first cruise in it was about 300km and it never went below min.