Mine doesn't have a light. He was in there about 6 months & did fine.
Of course originally he was in a tiny little thing that was barely 1/2 gal. And neither were heated.
The temp in the cube was around 72-75 & I knew that was too cold. He is in my office & we don't have much room.
So I knew it was going to take some thinking to make space for a tank.
When my office mate got the frog-death trap from Brookstone I knew I had to do something. Then the snail & 1 frog died & I knew we need a real tank.
So we found the space (actually she got a shelf from Home Depot) & I got the 3 gal. When I put him in & turned the light on - wow - he's so much prettier! I also have a heater for it.
We had a card board "lid" on the cube & it's pretty dark.
The poor frog was afraid of Freddy & he was eating all the frog food so the frog is now in the betta cube.
Because of how weird/tiny our office is - getting a desk lamp to light the frog isn't easy. But I'm still thinking.
Using a light for heat is bad because you don't want to leave the light on & then the water temp drops & that stresses the fish & they get sick.
You need at least a 2.5 gal w/ a mini heater to keep the temp stable.
I was worried about the frog being too cold - but it was either the betta cube or starve to death w/ Freddy!!
And it's been over a month & the frog is fine.
The funny thing (no haha) is at home I have a 6 gal eclipse, heated, filtered with plants & Fins (in my avatar) is at deaths door (ICH).
Freddy has lived in 3 different tanks at work - only the last one is heated & large enough - we have had him over a year - and he's great.
My "properly" cared for fish isn't