Yeah, it looks like you have t12’s — the fluorescent tube sizes are in multiples of 1/8 inch, so t8’s are 1” diameter and t12’s are 1.5” diameter. T12’s are least bright and need to be as close as 1”-2” above the foliage. This means 2 tube light fixture is not going to provide wide enough pool of light.
Things you can do to improve the situation
- remove the light tubes and double-side tape something reflective like inside of chip bags or Mylar or aluminum foil to line the reflector if it is not bright white or shiny. You’ll notice the difference right away when you replace the tubes and turn it back on. I have a grey reflector 4-tube light that I always line with Mylar (emergency blanket cut to size).
- You can also extend the existing reflecto — the one you have is a bit narrow — by crafting extensions with lined cardboard or something... or if the reflector is steel, you can use magnets to put up a shiny curtain/tent that drapes from the edge of the reflector to the base of the trays.
- You could also set up a reflective surface by lining the surface the trays are on.
- I also line the walls and underside of shelves above, etc. My “Garage V8 Nursery” is on an old 80’s black and gold lacquer dresser and the big mirror is on the wall to reflect all the lights right back.
...what you are seeing is one of the reasons I don’t like single connected sheet of cells — ones that can be separated can be shuffled around and rotated, so the seedlings are not leaning/reaching in one direction but are made to change directions. Flexing them this way will help strengthen the stems so is not a bad thing, but ideally, the light would be strong enough and evenly distributed so that they grow straight up. — some people will cut them apart anyway, even if they are not made to be.
...I also don’t like to start seeds in them because of the empty cells that didn’t sprout taking up prime realestate under the lights. I think it would be better to start them in something else, then transplant healthy seedlings that are same size in one tray, if using them at all... but even then they might grow at different rates and cause problems later when their heights become uneven and some are too tall while others are too short.
..... out of curiosity, are those blue strips rows of cells covered with masking tape?