The 2 together in your medium would be beneficial in two ways, supposing your temps stay low enough to keep them alive. Night crawlers are less hardy to the heat, which is why they burrow. In nature they can burrow up to 10 feet deep. If they can't stay cool enough it will cook them.actually you'd be surprised, I think the native earthworms do more for my containers than the reds, the reds just compost, and don't do much past the first couple inches of the soil, but the natives dive up and down, back and forth, making little gopher hole-type piles of castings.