new granite question

Hello,

I just had geen peacock Granite (http://tanbrown.org) (is it really
Granite (http://tanbrown.org) ?) installed today.  I want to keep it looking
great.  The installer put some sort of oily substance
he called a sealer on it.  Do I need to get it
professionally sealed again or will his sealer do the
trick?  Of course I found your site after the fact.  I
hope you can still give me advise on whether or not to
seal with a professional company and (http://maplered.com) daily maintance.

Thanks!