I'm currently nuclear red but I've been considering changing to blue. If prefer an electric to midnight blue but the only times I've been blue, it's been over a light blonde base.
Are there any blues that'll cover bleached out nuclear red?
In a word ... no.
At least, not straight away. Nuclear Red is orange based, and colouring your hair is like mixing paints--blue and orange equals mud.
You'd need to go around the colour wheel by putting a strong pink or pink-based red over the top, then go to pink-based purple, then blue-based purple, then blue.
Yeah, a bright true blue won't go over an orange, even a pale orange.
You can get a deep blue, navy type of shade with a dark purple based blue such as SFX Blue Velvet over an orange base.