What size tubs should I use for my auto's 5ltr or 7.5ltr? bought both

Question in the title...

Which one should I use.. I'm growing blueberry auto's

Also if I use the bigger 7.5ltr will I need to water/nute more than a 5ltr?

I've never done any autoflowers, so I'm not sure. Generally you should grow in as big of a container as possible, assuming the plant can take advantage of the medium. I would go with the 7.5L but that is just a hunch. You could always try one in each size pot and see if it helps.

thanks il await more replies