If anyone of you are still not decided where to go this summer, and just incase you have short listed Sri Lanka / Kalpitiya, then this might be of interest to you.
Note: For the ones who are not living close to Frankfurt, check "Rail and fly" option.
SriLankan Airlines : September and October
From Frankfurt nonstop to Colombo
Dates: Various dates in September and October possible
2 months validity; 30 kg baggage allowance
Price per person from 539 €
You can choose "English" on the booking engine.