Two possibilities — actually, there are more, but these two will be the easiest for you:
1. Make yourself the owner of the directory 
sudo chown sproid:sproid /srv/sproidssd
2. Leave it root-owned but give yourself write access
sudo chown root:sproid /srv/sproidssd && sudo chmod 775 /srv/sproidssd
If any other user accounts need write access too, add them to the sproid group.