I think the lighting affects the lightness of the green leaf.

This is the first time i see/hear about narrow red. Tropica like to name thier java ferns with some GTH names.

I do have several java fern forms. I believe one of the broad leaf version is the undulata. The emerse form has red tips as well. As for submerse form, its only slightly reddish and yellowish. But it does not carry the distinct leaf veins of a java fern RED. I believe this could be the undulata or so call broad leave version.

Another java fern which is imported as narrow leaf (from taiwan), is not really narrow at all. More like the normal ones but have better leaf vein definition. And under good condition, the center vein is slightly reddish. I never see it on the normal ones.