What did I do wrong? (Image composition)

[WoodenStove]

I wanted to make a bottle with ocean in it that is on the table in a sunny day.

Pictures were different dimentions and I think that made picture in some parts sharper and in some blury.

How can I fix this problem with difference in sizes? Can I do anything?

Here is the picture that I made:

Now it looks like Coke,not like ocean

[Derek Cross]

Seems you need to get a higher res ocean pic.

[SJRiegel]

Also, the perspective angle of your cup doesn't quite match the deck it's sitting on, and you will need to add the shadow that the cup would cast on the deck.

[Derek Cross]

Maybe make the cup a bit larger to emphasise the effect.