They do sometimes back way off in the heat. But they tend to start again as temps drop slightly and day length begins to shorten.
Keep in mind when talking of the spawn of FHM, females are laying eggs throughout the day, every day so you have fry hatching non-stop 24-7. Each individual female may lay again in 11-20 days but there are always active, egg-laying females at all hours, doing their thing.
