Please note that personal image galleries are limited to 500mb of disk usage:
ToS said:
Personal Image and Video Galleries
Personal galleries are limited to 500MB of disk space for images and videos.
Given that most of the space is taken by images used in a gallery form, this would count as a personal gallery.
That said, I have made a increase on the account, but you will not be able to get the amount you wanted (actually it would only be increased in increments of 0.5 gb regardless). Due to the nature of how you use the space currently, you would not be eligible for another increase if the gallery usage has gone over the limit as per ToS at a future date.
