Something is rattling under the car when i begin to take off.

What is your question?

I recently heard this noise and knew right away it had something to do with my tank or so i thought. so i got rid of that gas and put a different brand and with a higher octane level. Then i put some lucost cleaner in the tank. Now the noise is still there, maybe I'll try some octane booster? Im not sure but i know it wil become a problem eventually..... Any advice?