These girls haven't improved that much. Lowered the cal-mag
...getting fed 2 times a day.. @MIGrampaUSA
i'm starting to lean towards it's the T5..maybe not enough light?
I'm thinking its quite possible.
I haven't used florescent style lighting since the 80's ... and to me, a T5 is nothing more than a glorified florescent light.
For veg, consider something like this ....
In most cases, people usually don't need more light. They simply need to learn how to better use the lighting they have. Yours is probably the exception and an inexpensive upgrade would likely pay you a huge benefit.
You don't necessarily need a 10 pack. A few is all you need. They also can be found in 2' and 4' lengths which makes fitting your space rather easy. They zip-tie to anything from tent posts to pegboard so you can arrange them pretty much as you see fit.
For veg, look for cooler color temps like 5000k, 6000k, or even 6500k. Your plants with adequate lighting should progress from 3 fingers to 5 fingers and so on. Outside in natural light, fan leaves can get quite large!