1.5 or 2.25 fizzy drink bottle, bottom cut off, about 3/4 way down, leave the lid on the top part of bottle, tip it up, put your salted water in that, float it in the tank so stays a good temp, pegged to the side (that is what I do), put an airstone in, make sure it sits down the bottom so it moves the brineshrimp eggs around well, and bobs your uncle 8)