Repti Glo 5.0 T-8, 14w Repti-Glo 5.0 UVB Bulb fits a tropical terrarium lamp. For reptiles with high UV requirements. Ideal for all tropical and sub-tropical reptiles. UVA (30%) stimulates appetite, activity and reproductive behavior. UVB (5%) promotes vitamin D3 synthesis.
Would this be ok to grow cacti seedlings?
Yes, keep the light close and watch for stretching, it won't be strong enough for any real length of time though.
5% UVB bulbs are great for supplement lighting, All that high end blue and violet with the UVA/B gives them a good match for HPS, which lacks those frequencies.
A similar Fluorescent T8 bulb is Zoo Med's Naturesun, which has 2% UVB and a color rendering index (CRI) of 98. These will grow without any help but do need kept close.
For comparison a CMH runs a CRI of 92 and most HIDs have CRIs in the 80's.
ReptiGlo 5's CRI is 70, very poor deep red.
HPS, which has a CRI of 30, will benefit greatly from the UVA and the blue, the UVB is bonus.
2% UVB out of the total spectrum is plenty, but it is hard to get enough of everything else if using lizard lights all by themselves.
Mix and match, the cactus will love you.
