This package gives you 2,500 Gems in total. The +25% bonus is already included in that 2,500 - you will not receive 2,500 Gems and then an extra 25% on top.
What You Get
2,500 Gems in total, added straight to your account
That total is made up of 2,000 base Gems + 500 bonus Gems (the +25% bonus)