I would not recommend hatchets for so small a surface area. It is true that the species in Carnegiella (the marble is one, C. strigata) tend to be much less active, but even so I have seen them playing tag now and then and they do like space. They are also best with more in the group, say 9+.
I'm telling ya, dude... Invert Only is the way to go with a tank this small! You will love watching the shrimp, snails, and worms do their thing. That's why I mentioned the swim space... You can get very dense, and it won't affect inverts like it would fish.
I'm telling ya, dude... Invert Only is the way to go with a tank this small! You will love watching the shrimp, snails, and worms do their thing. That's why I mentioned the swim space... You can get very dense, and it won't affect inverts like it would fish.
Most fish eat shrimp. I'm not sure if that is a good plan. I've tried SAE and shrimp, and I found that the shrimp stayed in hiding most of the time. When I removed the SAE, the shrimp got active. Shrimp are at the bottom of the food chain, and they know it! If you ever want to see them and you don't want a hostile environment in your tank, skip the fish if you have shrimp.