Fruit Flies (Drosophila Hydei) 500 Producing Flies -- Enough Flies For 5 Cultures! Let Us Raise Fruit Flies For You.. Here's a Fantastic Deal !! 500 + Hydei (Flightless) Fruit Flies. YOU ARE SAVING on ... culture supplies ... and time. Actually you will have enough flies to make 5 cultures at 100 flies a culture! Or you can use them to bulk feed your livestock. WARNING: If you live in an area where the temperature is dropping below 45 degrees during the day, please contact us regarding the need for a heat pack after you make your order. Transit time is usually 2/3 postal days.