The general rule is that species with red leaves need more light than plants with pale green leaves, and plants with pale green leaves need more light than ones with dark green leaves. The science is to do with the density of chloroplasts in the mesophyll layers of the leaves, and the amount of accessory photosynthetic pigments in addition to, or instead of, chlorophylls a and b.
Specifically, the red pigments in plants are usually anthocyanins, and these exist to protect the cells from UV damage under intense lighting. Most plants have them, but you don't usually notice them because the chlorophylls are more common. Anyway, some plants have less of the chlorophylls and/or more of the anthocyanins, and these appear red. Plants in moderate or low light intensity environments don't need the anthocyanins so much, so don't have red leaves. In some situations, plants that have red leaves when grown under their normal (bright light) conditions produce pale green leaves when grown under less good (weaker light) conditions. In this case the plant is "economising" by not producing pigments it doesn't need.
If you find it difficult to grow plants with red leaves, try choosing plants with light green or dark green leaves instead. Alternatively, look at some of the Cryptocoryne species. You will find hardy varieties such as C. wendtii that have reddish-brown leaves that actually do fairly well under moderate light. Sure, they aren't pink like Rotala or Alternanthera, but at least they'll live in your tank.
Cheers, Neale