I would say a tank of those dimensions is nowhere near big enough for a Mali. Our Occellated pair are still only young and are startingto look cramped in one of similar size. Something 4x2x2 as a minimum
for one and then 5x2x2 or over for a pair i would think.
The best lighting would probably be a Megaray bulb or other similar ballasted mercury vapour lamp to provide optimum UVB, and perhaps additional heat because they like it HOT! You could probably get away with using flourescent tubes or compact flourescents but the amount needed would be pricey and you would end up spending as much as the cost of a megaray anyway.