In Thea it will help if you don't use IOR 1.0 for pool walls and floor.

I also think that changing the name doesn't change the fact that Thea is in fact nothing more than a newer commercial version of Kerkythea. But I could be wrong as I personally have little knowledge of it - only what I read between the lines in the statements I can tell, you are wrong. :wink: When ...

Unfortunately, Sketchup doesn't have a subdivision tool so I am stuck with a low poly model. I already cranked the smoothing values down (to that level the model gets tesselated) so I am not sure how to overcome this. Would lowering te fresnel value (1 is default) solve the problem? Cheers, Kwisten...