Nick,
Congratulations on the new arrivals! I haven't had experience with T-5's Just T-12's. I know that Phals do well under T-12's so be careful not to get them too close to the bulbs! I would wait to re-pot until they're done blooming. just be careful not to over water them. (Or under-water!) Moist, but not wet.
Great to have you with us! Let us know how the lighting goes!