Today I was repotting and I discovered one of my Phals in semi hydro (it took to it the best) has started spiking. I just wanted to say a giant thank you to every body here for all the advice and answers.
Really, did they die quickly? Some of mine are struggling, lost a lot of roots but I think its to do with the vendors. They were not the healthiest plants to begin with. But this baby is loving it. I dug it up to plant it properly and the roots, they were like weeds. I am so delighted. It will be a while before I move any more to semi hydro but my aim is to have as many in semi hydro as possible.