Hi there! I have found a circular light from a local electrical shop, it is 8000K colour temperature and the cost is only US$5.45.
Spec. for NEC After Glow 3-band Type Daylight Color( FCL32EDF/30-SHG )
" With a color temperature of 8,000K EDF-SHG* lamp emits light that emphasizes white colors and creates a cool, refreshing and clean-looking ambiance. This lamp is better suited to situations such as living rooms, bedrooms, corridors and kitchens where lights are turned off last of all. "
After installed and tried for a week, plant grows and carpet plants producing O2, compare to existing Philips 32W circular not doing so well.
Spec. for NEC After Glow 3-band Type Daylight Color( FCL32EDF/30-SHG )
" With a color temperature of 8,000K EDF-SHG* lamp emits light that emphasizes white colors and creates a cool, refreshing and clean-looking ambiance. This lamp is better suited to situations such as living rooms, bedrooms, corridors and kitchens where lights are turned off last of all. "


After installed and tried for a week, plant grows and carpet plants producing O2, compare to existing Philips 32W circular not doing so well.