I used a plastic 1kg empty peanut butter jar. Make a hole in the lid big enough to fit an airline tube through. Put a diffuser on the end of it. Make a wire handle around the neck of the jar so you can hang it over the edge of your main tank so extra heating not required. Half fill the jar with required salt mix and eggs, turn the pump on to aerate well and wait. When I wanted naupli, I just turned the air hose off, waited for it all to settle, then used a turkey baster to suck up the naupli which were hovering in the middle. These I squirted into a white hanky over another jar so I could then rinse then drop them into the fry tank by dipping the hanky in. The rest of the mixture from the batser got poured back into the jar and the pump turned back on.