20watts enough?

some java fern and moss attached to the wood directly under the light. It may hold its own but not flourish. Maybe an anubias would do OK under the bulb. Keep the photo period long, like 14 hours a day.
That light that mg linked is the best deal I have seen out there for t5 lighting.
 
Not dying and flourishing are two different principles though. If your only goal is for it to not die, then your light will suffice. If you have any desire for your aquarium to flourish, then get better lighting.

I've kept Java Moss alive in a similar setup for over a year.
 
Not dying and flourishing are two different principles though. If your only goal is for it to not die, then your light will suffice. If you have any desire for your aquarium to flourish, then get better lighting.

Yah, I know. I'm aware that it wouldn't grow, but I'm saying it will stay alive.
 
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