Resolve speed of object falling

Hello There, Review the url - [login to view URL] It has many configurations already and it works almost flawless. I need some changes to be done as below. 1. Initially it started with actual speed, but after some seconds, say 5-6, it became very slow like screensaver. 2. Can we do like single type of bubble - bubble with photo, would not be replicated more than once on a screen ? I mean to say there would be unique photo only on screen, once that is off the screen, it would be repeated with unique content only. 3. Sometimes performance issue while feature is working for long time. 4. Sometimes bubbles gives a jerk while falling/or on collision. 5. Falling of bubble and movement after collision does not seem realistic sometimes. You need to review and understand the script completely then only send proposal. If you are really good at JS/Jquery, should not require more time to complete. Send some analysis with proposal to be considered. Thanks, Parag