Tokens are being sent out while crowdsale is still ongoing? If that's the reason you chose to give out 5 OBIO per participant, you can as well just increase the number of OBIO per airdrop participant and then delay the payment of airdrop until after crowdsale. A lot of people are not joining the airdrop because the amount is small and then you are not asking airdrop participants to retweet the airdrop tweet on tweet to get to more audience. More audience will attract more airdrop hunters and as well investors. Good luck with project development