If you need to grow bitcoin i suggest not to put it on any investment sites now because it's very tempting to them to turn to scam because the price of bitcoin is continue rising. So i were you i will just increase my bitcoins by signature campaigns.
yes. but I am seeing you are not in signature campaign? whay?
anyway. you are right in that manner that investment at this time is not good. (actually it good if you can find a legit way) because there is not any legit way or almost all sites are scamming sites.
so staying away from them and growing your bitcoins for your activity such a from signature campaign or your daily tasks and services is best choice.