You don't really need another light but it could help. UVB is more important than UVA because it is the UVB that is needed to synthesis vitamin D3 which helps prevent things like MBD. UVA helps to stimulate normal behaviors like feeding, ect. If your lizard is acting normally then a UVA bulb is not overly necessary but when you replace this bulb I would get one that is both UVA and UVB. Hope this helped.
Charlene
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