Hi. You could spread some straw or hay on the surface for mulch. It will settle down a bit once watered in and also slow moisture evaporation from the surface. Some frown on using hay as it may contain weed seeds that could sprout which doesn’t make sense as we are growing a weed. I just use Timothy Hay from Walmart. Cheap and effective especially if you have gnats.
Red stems could be from genetics. My GDP had red stems from sprout but eventually turned to normal.