Thanks Ahh yeah it is...I'm so tired that I've forgotten how to distinguish between different numbers
It won't only be 4OH- if it's in excess!
EDIT scratch that the book says it would be 4OH-
2nd edit, I also thought I saw it with 6 in past papers, so I don't know tbh
3rd edit, just found this on the AQA chem 5 page for wiki books and it says it goes to [Al(OH)6]3- in excess OH- but tbh, both would form a colourless solution