I agree with Carlos, you need to be careful because the dominated smaller guy will eventually develop issues from both the stress and malnutrition.

I'd be a bit more liberal with the food dispersion. Not the amount, but the dispersion, giving both of them separate directions to go in.

Also consider live foods too for you lil guys. Many live nematodes will live inside the water for a period, giving your smaller guy a longer period of time to feed without destroying your water conditions. If they are eating bloodworms, you may try Grindal Worms, which culture on peat moss or coco fiber and feed on nearly anything. Microworms and Vinegar eels may work too, but I think they could be too small.

California Blackworms are a really good bet too! I have a care sheet here if it interests you...
California Blackworms (Care & Culturing) - Small Pet Feeders (English)

I vote for a larger tank too, give them some room to claim separate homes if they want.