Before I moved to LEDs and pressurized CO2, I was using 4 T8s and dosing Excel. Ludwigia repens x arcuata and Ludwigia sp 'red' were both growing well for me. The L repens x arcuata was green, but doing good. The L 'red' was still red, but not as red as it is now with higher light and CO2.
I also had/have Ludwigia ovalis and it did just OK under the T8s.