White worms on the galss are planaria. Every tank probably has a few. The become noticible when you feed too much and don't do enough water changes/tank maintainance.
Planaria are easy to get rid of - when you don't have babies in the tank . . . . Right now you're doing less water changes and feeding tiny food for the fry. All things planaria love.
Otherwise you'd wipe down the glass, thermometer, cords, inside the filter box, filter media and do big water changes while cutting way down on the food for a week or two and the planaria would disappear. . . . Unfortunately your fry would probaly disappear too . . . .
I'm not sure what to advise you to do. . . Do you have another tank you could set up for the fry and parents?
Carol