I give up

You know you don't need to do that all at once when you feel lie it you can do it or simply if you ever come across them mark them

^I agree, that's what I did (and still do) also if you find a list or search through the tags it's easier to mark the ones you remember since the 'read' buttons are right under each one

I did not know that, thank you very much!

Don't do it, I did that and spent lots of time adding loll then now Iam regretful because I can't find things that I really like and I can't know if I read and enjoyed or just clicked read because it was too bad and don't want to bother with it again. Tagging is your best option

Thanks for the warning! I'm finding that when I add manga to my lists I tend to give ratings only to the ones I really like. This might help me keep track of those better

Yep also tag them so whenever you feel like rereading you will get them back faster