Color gel to match strobe to speedlights

I have a single studio strobe that I want to use as my key light with a reflector for fill. In addition, I want to use a pair of speedlights for the white background and another speedlight in a  small softbox for a hair light.

The light color is strobe is different than the speedlights. It's about 300-350 degrees warmer and +20 magenta.

I can't gel the strobe but I do have a wide variety of gels for the speedlights. CTO, CTS, green and blue all in 1/4 1/2 and full cut.

While I can fix some of this in post processing, I'd like to get the colors as close as possible in the studio. It would seem that I need the opposite of a CTO but I'm not sure what color I need on the speedlights or what cut.

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-Dan Rode
http://rodephoto.com