Once your beer is fermenting, I don't know that you want to add water - that will just give you a watery/thin beer with low gravity. I guess, I would just let it go, let it ferment out for about 3 weeks total. Maybe get another bucket - just a 5 gallon one - and use it as a secondary and let it sit for another 4-6 weeks in that. Then, taste it. Probably, your best friend here is going to be time. Any kind of "spice" beer tends to mellow out over time. I have made some beers (pumpkin, christmas, maple) where the flavors were just overwhelming at first, but mellowed out over time and became quite drinkable. After you let it sit for the time in secondary, you will have to decide if you want to bottle. If it seems closer to something you want, bottle it - it will still continue to mellow out. If it is just horrible and you can't stand it, I would dump it and chalk it up to experience.