At this point your brine shrimp are extremely tiny, smaller than a pins head since they are still babies. To grow your brine shrimp onto adulthood, you must feed them. For the first 24 hours of life your brine shrimp will not require feeding as they are still relying on their egg sac, and have not fully developed their digestive system. Brine shrimp are non-selective filter feeders (meaning they're not fussy) and can be fed a wide range of foods, including but not limited to Liquid fry or similar fry food, yeast, whey, wheat flour, soybean powder, fish meal and egg yolk. The criteria for suitable foods are small, easily digestible particles which do not dissolve in water (for example, powdered milk won't work). Most importantly, do not over-feed them! In the small capacity of the soft drink bottle, it is very easy to foul up the water with excess feeding.
Depending on water conditions, foods and the strain of brine shrimp you are raising, it could take anywhere from a week or so to a month to reach adult size. How long, or more accurately, to what size you raise your brine shrimp to, is up to you!
