There's not a lot you can do post-fermentation, but let's get some recipe and process information (in as excruciating detail as you can give it) before we condemn your beer to death.
Wits are not known for their body. Mash temp could be killing you as could fermentation temp. The more info we have the better chance we have of helping you- now or for future batches.
I can't be arsed to keep up this list of what's in the fermenters, but hey, check out the cool brewery I own!
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