Bandwidth limit exceeded

[CENTER][COLOR=Gray][/COLOR]Hey all, well i made this web:
www.prismaestudios.com
it used to have 500 mb of bandwidth but it has reached the limit
but isnt too much???
now it has 1000 mb, someone can tell me why it uses so much bandwidth???
i have like 18 galleries with an xml code to load each one of them do u think is that?
how can i fix it!

[LEFT]tnx
[/LEFT]
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