"Do these plants look like they're ready to be harvested?

No, they do not.

" i have not looked through a magnifying glass at the trichromes"

Then I suggest that you obtain a glass and employ it.
They are under $10 and will save you many times that.

The leaf shape says Sativa.
It could take up to 12 weeks to fully mature a sativa kine, and the pistils are not a good indicator of ripeness.

"then what might have caused their lack in density?"

You are trying to flower with ~15 Watts per panel.
It can be done, but not well.

LEDs are efficient, but they are subject to the laws of physics.
There are simply not enough photons to grow fat, dense buds.
Those crappy panels are barely suitable for cloning.
Triple the power and you'll grow some half decent bud.
These were flowered under 55W. of red and blue, 3W. LEDs



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