Light levels for Phal gigantea?

[camille1585]

I got a Phal gigantea last fall, and so far, it's doing pretty good! I've had it 6 months and it's already grown one leaf and just starting another I just wish it would start some new roots (the existing roots are nice and healthy, but not very numerous) to support the increasingly massive leaves.

I know that this species can take A LOT more light than most other Phal species, but how much is enough? I have it in a south window where it now gets something like 6 hours of direct light a day. I'll either pull it back from the window a bit or add a sheer curtain as the strength of the light intensifies (Just so you know, the Netherlands is level with southern Canada, so not extremely strong sunlight, but still enough to burn in the summer).

The leaves are now a light yellow/green. Is that too much for it?