The thing you could do to just grow them in a slow but safe way is signature campaigns right now.
Also because of the risings the pay out rats of some sig campaigns is pretty nice and profitable but its depending on which campaign.
Is there a link that lists all the campaigns with their rewards?
find it in service section, if you have a high rank or atleast member/Full member you can join yobit campaign signature they give you more bitcoins not like other campaigns and they pay daily, 20post per day so if youre full member you can earn 0.004 a day by just posting in this forum , but you need to be careful what you posting do not spam or copy paste.