To make sure that they get along, use skinks of a similar size and species. Enclosures can have several females, but males will tend to compete with one another. As a result it's best to give new skinks a trial run to see if they get along with the other skinks before moving them in permanently.
The difference is that a skylight filter is a basic colour correction filter with a slight magenta tint which has a similar effect on skies as a UV filter (which cuts out part of the spectrum), which is neutral coloured.
Rosco CTB Blue overview. Roscoe Full Blue CTB Color Conversion Gel Filter - This filter is traditionally used to convert tungsten lighting to daylight. CTB (Color Temperature Blue) filters are available in a full spectrum of degrees (strengths) which, depending on your needs, can be used to either raise the temperature of your lighting or to create different lighting interpretations. CTB filters offer you complete control when shooting under tungsten lighting.