Join Date: Jun 2010
Location: Northern Virginia
With the betta's temperament permitting, they should do well. It makes sense to me that adding the cories first would help minimize the betta's response to them. If you added them awhile after the betta, the betta would see them as encroaching upon his territory and act accordingly, especially if he has had time to build a bubblenest and feels the need to defend it.
It also makes sense from a biological standpoint to add the cories first, assuming you're doing a fishless cycle on the tank beforehand, which would certainly be the best way to go about it if you're planning on stocking the tank with a whole school of fish plus a betta.
You could feasibly put in 6 panda cories with the betta, assuming you're using a decent filter, and you would be about 80% stocked, but with 6 pygmy cories you would only be about 70% stocked. I usually recommend pygmies for small tanks simply because you can fit more in, and the more you can fit into a school of social fish, the better. You could use the pandas and still get a decent school if you're set on those, though. :) If I were you, I'd go with 6-8 instead of just four and try to pick a sand substrate like Flourite sand.
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