for L. Brasiliensis high light (around 3WPG or more) high co2 levels (20-30 PPM) and a good dosing routine are vital, it wont handle temps over 26C, best way to get it to grow on is to seperate it out as much as you can and plant the individual plantlets 1-2 cm apart, its a relatively slow grower, and can be slow to establish, it is also very prone to getting algae on the leaves if the conditions arent right, id recommend setting up with no fish beforehand so you can have higher co2 levels, that will help the plants and prevent the algae from growing, you might want to try L. Mauritiana, its a much much less demanding lilaeopsis that will grow in a wider range of temps and conditions, L. brasiliensis, mauritiana and macloviana can all tolerate low salt concentrations.