I have received wonderful advice on how to count rays However my close up vision stinks, and I can't see the tail close enough to tell. Here are pics if anyone cares to help....
The orange one is a VT. The others might be VT or PK (females not males). If you breed a PK female to a VT male you will get VT fry. Agreed with newfishy they look like combtails, especially the blue one.
I've found that most females tend to have a bit of ray-extension making them look like combtails (on the caudal fins). But, the dorsal of that blue does seem to have this too so she might be a combtail. The others are likely VTs.
Where did you get them from. If it's from a pet shop, then I'd assume VT for all of them until proven otherwise
I'd say the top is a VT, the two bottoms appear to be from a VTXCT cross as you can see the ray extensions, but they are still VTs...not true combtails yet.