I'm guessing this is too late now but if your fry got sucked into the filter intake you could probably try fishing it out of the filter and it might still be okay. I pulled a 2 week old fry out of my filter sponge last week when I did maintenance, don't know how long it had been in there. There was just a tiny orange tail sticking out of the coarse sponge and I thought it was dead but it wriggled free and swam off when I prodded it!