I also depends on the depth of the tank, whether 2 x t-8's would be medium light or not:
PAR vs Distance, T5, T12, PC - New Chart
29 gallon, Fluval 306. Aquatop PF25-UV Power Filter, 1x39 watt T5HO 7" above tank. P.F. Sand, Pressurized CO2, 5 Glowlight Tetra's, 3 Halequin Rasborah's, 3 neons, 2 Oto's, 5 Cherry Shrimp, 4 Amano Shrimp.