Beer you use for gravity measurements

Just to clarify, when you take gravity measurements, do you ever pour the beer back or just discard it after the measurement? Also how much liquid is usually necessary for a good reading?

Don’t risk contaminating the beer by pouring it back in. Drink it for quality control.

Even the wort gets tasted. Some may be discarded instead of consumed.

Test the volume needed by using water.

+1^^^^

Never pour it back - that is just begging for an infection in your beer.

Thought so, but I’m choosing to ask all the stupid questions early on. Thanks guys!