Sterile as possible, soilless high-porosity mixes. PromixHP I've used, and is outstanding. The Fox Farm Light Warrior is the ultimate, people I trust here and the hydro store say the same thing.
Past the fact of clean soilless, whether the media is pre-charged with ferts becomes the second consideration. If it's not charged, then a nutrient plan needs to be in effect from just after true leaves emerge.
I've also germinated in all the following easy made mixes to good success:
peat or coco-coir, or in a blend, and 30%-40% perlite
DE straight: diatomaceous earth, ie floor dry
50% perlite/ 50% vermiculite
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