Hello.
This summer I had about 600-700 Yellow-perch fry in my little pond.
I had 10 tanks for the spawning of Culex, every 3-4 days I collect the rafts and put them in the small pond and this during the whole summer, so it makes much more than 100 rafts, the eggs hatch in 3-4 days depending on the temperature.
That's a lot of mosquito larvae.
A+