gypsum in the mash

I'm planning on doing my first all-grain brew tomorrow i've done a lot of planning and researching so I'm hoping all goes well. I'm a bit worried about one thing though, I forgot to get some food grade gypsum for the mash water. I filtered all my water through a brita water filter because my tap water doesn't have the greatest taste in the world and i'm not sure if that would filter out any calcium that might already be present in the water. There isn't a homebrew store in my town and I don't know where else I may be able to get gypsum for brewing. My dad has a bag of gypsum which he adds to the soil in his garden once a year, would that work or is it probably not food grade? Are there any possible subsitutes which are easily accessible which would add the calcium ion to the brew? Ok, one last question, should I even worry about this or will my enzymes do just fine without adding gypsum? Thanks.

Austin

What are you brewing.......You probably dont even need it.

I agree, you probably don't even need it. We have no way of telling unless you could provide us a copy of your city's water report.

What do they say? RDWHAHB? Yep! Your mash will be fine and your beer will turn out great!

I'd also agree about not adding gypsum unless you really know that you need it.
Don't use the agricultural grade gypsum. Not only is it not food grade, but it is also not pure gypsum. It has all sorts of other thing in it which won't hurt the garden, but which vould hurt the brew.

-a.

Rdwhahb!!!!

Found this report:
http://pangea.stanford.edu/courses/gp104/waterscape/viewscaperk.php?entry=34
It does look like pretty soft water. I don't think you will have a problem with soil conditioning gypsum:
http://www.pacificcalcium.com/products/gypsum.html
You might even find the same info from that particular supplier.