Very nice setup. You did a great job.
This is not a wattage question, but rather a light intensity question. 58 watts is related to light intensity within the flourescent tubes, but even then there are important differences among the different tube bulbs. Factor in different types of incandescent, halogen, and self-ballasted bulbs and wattage becomes an even less useful measure.
You need to find the right light that is neither too bright nor too dim for the plant species you have in your paladrium. That's what you want to know, correct?
This sounds like a question better asked to a plant person and not a cage construction and design forum.
But perhaps someone here will know.
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My tank is 3ft tall by 1.5ft by 1.5ft, its currently on 58W (1 36W and 2 11W tube) pls advice if that's sufficient and how I should calculate the amount of lighting I need to have for my other tank.