Fry are amazingly tough. I found a tetra fry in a tank that I'd tossed some plants in to hold over until I was ready to plant them. 3 months later, I still hadn't gotten around to planting, but I saw a fry. No filter, no water changes.. brown gunk from the nasty substrate being strained through the water... no telling what the parameters looked like. It's still kicking it a month and a half later.
"What, exactly, is the internet? Basically it is a global network exchanging digitized data in such a way that any computer, anywhere, that is equipped with a device called a 'modem', can make a noise like a duck choking on a kazoo." - Dave Barry