Join Date: May 2013
Location: Massachusetts, U.S.
First of all, they are sensitive, and definitely should be put into an already cycled tank.
Second, I have 5 Cories in my 10 gallon, but I am overstocked with them. Really about 3 might be your maximum without overstocking. Though you also have snails. 3 Cories is the minimum that should be kept in a tank. So for everything together, you're gonna need to do big water changes. I do at least 50% every water change, sometimes more. And my Cories aren't adults yet. Some day they will be in a bigger tank, though. I just need space for it.
But yeah, you would need at least 3 but you would be pushing your stocking level.
Though people have varying opinions on stocking levels. My Cories are doing just fine the way they are and are active and healthy. I just have my shoal of 5 with my VT Betta boy.
2 Boys: Benedict (VT), Ramses (King PK) 3 Girls: Gylfie, Sonata, Alice (all VT) 5 Cory Catfish: Sherlock, Watson, Mycroft, Howard, Gimpy