It might be lilaeopsis, it's called micro sword too. Am I reading this right, your substrate is 30cm deep? If so you need to take out around 28cm of it. Emmersed growth will be easiest for you, aquatic plants need co2, as do all plants. Some substrates produce co2, like mine, but some people inject co2 from a canister. If you grow them emmersed they can access as much co2 as they need. Just keep the humidity up with glass lids od glad wrap.