I've been running version 6.1.0.3 since November and my disc usage has been fluctuating up and down about 10-20mb per day. Yesterday my disc usage increased by over 100Mb with no changes made to the board and an average day of posts. I contacted my host and they informed me:
"The disk space has been concentrated in:
/www/ubboard/cache-7WUGZ2TM"

I do have the accelerator on and up until yesterday it was showing about 55-60% of pageviews were from the accelerator....last night it dropped to 45%.

Any suggestions on how to reclaim the disc space. Do I need to clear my cache?

My UBB is located here

Thanks!