I have 3 neons and need to slowly add to their school so I'm aiming for up to 8. The tank has been running several years, and the neons have been in residence about 4 months. It is moderately planted with real and fake plants. I would like to add some cories. Is there a species preference for this size tank and the neons? Also how many would fit with that stocking as I understand they like to have friends. I used to have pygmies, which I love, but they are harder to get here. Thanks.