what is minimum trading lot size to move spot forex price?

Hi,
I am new to forex. what is the possible minimum trading lot size of market order to move spot forex price like 1 tick or 1 pip? 0.1 lot? 1 lot? or maybe 30 lot? Because, I can only observe the level 1 bid and ask price but I cannot see the order size. Thanks for help.

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Depends on Liquidity.

Hi Tjpld, thank you for replying. I digged around last night, and I noticed the lot size could be 30 or 3m units during low liquidity period. From fxcm's FAQ, it says if the order size is over 30 lots or 3m units it could get partial filled during quite hour. Well, if it is 30, then I don't need to worry about this at least now. Or any other suggestions about the size? Thanks a lot.