01-16-2010, 01:22 PM
| || |
There are so many species of Corydoras, I suggest you check them out before buying any just because they are locally available. You may decide you prefer others. On number, 6 would be fine, and probably my recommendation in your 20g with what you have.
The "emerald" corys are sometimes not true Corydoras. Corydoras aeneus is often seen under common names like Bronze Cory, Green Cory, Emerald Cory, and others. But a similar-looking fish, Brochis splendens, is also commonly named "Emerald Cory" even though it is a different genus. Brochis get larger than Corydoras, and that is a concern in smaller tanks.
I prefer buying fish locally so I know what I'm getting, it is relatively healthy, and I don't have to fuss over problems related to shipping (winter weather is a concern as you mention).