There is heaps of info regarding soil for various plants but to be honest with trichos they will grow in just about anything. They really like a slightly alkaline mix so add some garden lime to it to adjust the PH. Trichos love water and ferts in the growing season so give them plenty of both.
Give it a few weeks and they should be fine to re-pot. I have just done some of mine so I guess that says something about their hardiness, it is still about 6-10deg at night here.
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