Small: 3.5 – 4 inch standard nursery pot.
Small HB: 4.4 inch hanging basket.
Medium: 5 – 6 inch standard nursery pot.
Medium HB: 5 – 6 inch hanging basket.
Light
Keep your string of hearts in bright light, with some direct sun (but not all day) for the best colour and plenty of leaves.
If you notice large spaces between leaves, the chances are the plant is not getting enough light.