I've got what I think is L. thwaitesii (it hasn't flowered yet) growing in the a greenhouse. It's done best in a well drained pot with soil. In the past I've had it in a clay based substrate in a small indoor stream feature as well as in the above soil with a self-watering dish under the pot. As soon as I took the dish away and let the pot drain after its daily watering new leaves started growing. I'm hopeful that it will flower sometime this summer.
After trying the different types of substrates and growing conditions I'd have to make the guess that these plants prefer a loose substrate with decent circulation. They may be a good candidate for undergravel heating as well.