Conclusion

My hypothesis was correct. But my order was not correct.

The water weighed different amounts. 

I thought heaviest water to lightest water would be

1. Kiawah Island Lagoon
2. Flint Creek
3. Tennessee River
4. Pacific Ocean
5. Atlantic Ocean
6. Hartselle Tap Water
7. Los Angeles Tap Water
8. Distilled Water

My water weighed either 0.8 ounces or 0.9 ounces.

These weighed 0.9 ounces

1. Kiawah Island Lagoon
2. Pacific Ocean
3. Atlantic Ocean
4. Distilled Water

These weighed 9.8 ounces

1. Flint Creek
2. Tennessee River
3. Hartselle Tap Water
4. Los Angeles Tap Water

It wasn't as interesting as I thought it would be. I wanted the differences to be bigger.

I am most surprised about distilled water. I thought it would be the lightest because it doesn't have as much junk in it as the other kinds of water.