Someone told me that it's *necessary* but I took it out after seeing how dim it was compared to other bulbs. I'm wondering if it was a defective bulb. Which brand do you use?
All true actinic t5 bulbs are low par bulbs. The best out of the bunch however is the UVL super actinic. If you want something blue the ati blue plus are really bright but are not really actinic bulbs.