So, A while ago I decided that I had to try out the new OS X El Capitan, but I didn't want to do a full wipe of my computer, so I just made a partition on my main OS X Yosemite Hard Disk. Everything was working great, BUT I was running short of memory on both the OSs so I decided to simply delete the El Capitan Partition. BIG mistake. It deleted just fine, but now I can't expand my Yosemite partition, and I can't create a new, empty partition in place of the old one either... So, my question is: What should I do next? I have no problem in reinstalling the whole OS, but I am unsure if I would be able to merge the partitions even in the installation mode. Thanks in advance!