There is no right or wrong answer when it comes to deciding how much weight to use for barbell rows. The key is to find a weight that challenges you and allows you to perform the exercise with good form.
If you are new to barbell rows, start light and gradually increase the weight as you become more comfortable with the movement. You can also experiment with different grip widths to find what feels best for you.
As you get stronger, you will be able to handle more weight. But be careful not to go too heavy and sacrifice your form. This can lead to injury and won't help you build muscle effectively.
Ultimately, the best way to figure out how much weight to use for barbell rows is trial and error. Start light and gradually increase the load until you find a challenging but manageable weight that allows you to maintain good form throughout the exercise.