They do best with colder temps in winter, between 40-60°f  does very well. Bright conditions if possible. Andean winters tend to be cold and wet, but most temperate climate growers keep them dry in winter.

For pot size 8" is very small. More root space equals better growth.

They can take cold down to about 25°f min, with some forms able to survive 15°f, but that is rare.

Best to keep them above 40°f if you want to play it safe.

If using HID lighting aim for 40-50w/sq foot coverage and place as close to the light as possible without overheating, lighting from a diagonal side position works better than overhead.