je, slažem se da gro-lux daje pikove u određenim valnim duljinama ali naletio sam bio jednom na nekakav test groluxica i 4500 ili 4700 lampi i bilo je prilično slično (osim tih pokova). Zato i kažem da su groluxice OKO 4500.
Ali u svakom slučaju je dobro da si to napomenuo 
Na100 mjesta 200različitih informacija za sylvania grolux

Čak se na nekom forumu postavljalo pitanje da nisu 8000K+
Ovo sam ja našao:
Flourescent tubes, 48"
Lumen Watt lm/watt Kelvin Hours Manufacturer, Name
4400 60 73.3 3000 12000 Sylvania F48T12/D830/HODesigner
4250 60 70.8 4100 12000 Sylvania F48T12/D41/HO Designer
4250 60 70.8 3500 12000 Sylvania F48T12/D35/HO Designer
4250 60 70.8 4100 12000 Philips F48T12/SPEC41/HO
4250 60 70.8 3500 12000 Philips F48T12/SPEC35/HO
4250 60 70.8 3000 12000 Philips F48T12/SPEC30/HO
3700 40 92.5 5000 24000 Philips F40/AX50 Advantage X
3700 40 92.5 4100 24000 Philips F40/AX41 Advantage X
3700 40 92.5 3500 24000 Philips F40/AX35 Advantage X
3700 40 92.5 3000 24000 Philips F40/AX35 Advantage X
3600 40 90.0 5000 24000 Philips F40T12/ADV50/ALTO
3600 40 90.0 4100 24000 Philips F40T12/ADV41/ALTO
3600 40 90.0 3500 24000 Philips F40T12/ADV35/ALTO
3600 40 90.0 3000 24000 Philips F40T12/ADV30/ALTO
3500 40 87.5 4100 20000 GE Staybright
3500 40 87.5 3500 20000 GE Staybright
3500 40 87.5 3000 20000 GE Staybright
3400 60 56.6 6500 12000 Philips F48T12/D/HODaylight
3300 40 82.5 3000 20000 Philips F40T12HomeLightWarm
3300 40 82.5 4100 20000 Sylvania F40/D841 Desi800
3300 40 82.5 3500 20000 Sylvania F40/D835 Desi800
3300 40 82.5 3000 20000 Sylvania F40/D830 Desi800
3300 40 82.5 4100 20000 Philips F40/41U Ultralume
3300 40 82.5 3500 20000 Philips F40/35U Ultralume
3300 40 82.5 3000 20000 Philips F40/30U Ultralume
3280 40 82.0 5000 20000 Philips F40/50U Ultralume
3200 40 80.0 4100 20000 Philips F40T12HomeLightCool
3200 40 80.0 3500 20000 Philips F40T12HomeLightWarm
3000 40 75.0 6500 20000 Sylvania F40/D865 Design800
2325 40 58.1 6500 20000 Philips F40DXDaylightDeluxe
2250 40 56.3 5000 20000 GE F40/SUNSunshineFullSp
1900 40 47.5 3050 20000 GE F40PL/AQ/WS Plant&Aquarium
1875 40 46.9 3400 20000 Sylvania F40GRO/WS Gro-Lux1600 40 40.0 na 20000 Philips Agro-Lite
800 40 20.0 6750 20000 GE F40PL Gro & Sho