Everything is black, except the 1/4" and 3/8" tube fittings which are white, they are thick plastic but I don’t think they will block light out, they are the same sort of fittings u for RO systems, except I have found black tubing rather than white. I do wonder if they block out light that causes algae as they are made to be used with drinking water. But I will probably paint them black,or wrap them in black pvc tape