Ive raised a few thousand clowns. 8 different species. A few things I'd like to touch base on here.
Also, the eggs should not be exposed to air ever! If they where transfered to another tank via pulling the rock out, bye bye eggs.
All of my pairs spawn on a tile. Every batch, the tile has been pulled from the tank and walked 20 feet across the room to the hatching tanks. I dont set them on the table to allow them to dry out, but I dont worry about them being exposed to the air.
Honestly raising baby clownfish fry is difficult and requires you to raise food, rotifers and culture phytoplankton then they need newly hatched brine. I considered trying when mine began spawning but it is very involved and requires a lot of extra equiptment, I decided to hold off for now anyway.
one of the very best web sites on breeding fish has a tendency to scare people away ( IMO) because some of the members make everyone believe that it has to be difficult and has to be done a certain way. Many/most of those people, including the board members are very good friends of mine and there is a lot of great information to be had on that site, however, it doesnt always have to be as difficult as some of them make it seem. For instance, I do not grow/culture any phytoplankton and have raised a whole lot of babies. I use rotifer diet from Reeds mariculture. Some of the posts on that site will insist that you have to have 3 types of very clean phytoplankton cultures to be successful. I say poppycock! They say you need elaborate breeding/larval systems. Mine consists of a simple 5 gallon tank that usually only has 1-2 gal of water in it for the first few weeks. At a few weeks, they see their first cheap sponge filter. Yes, live foods (rotifers/baby brine) are needed, but they are simple to do. Very simple.
I feel that everyone should at least give it a try if they have a spawning pair. Someday we may not be collecting any fish and need/want every captive one we can raise.
all that being said, I agree that you will not have much success with this batch