Something is going wrong. Can any one help?

[nibbler]

I am having problems with some of my phals. Three of my phals are fine or I believe to be fine. I have included a picture of the root system of one of them. I am doing the same in all cases.
Three others arnt. A few weeks ago I placed one in water to water it rather than holding it under the tap. The second one I bought in a shop that was being drowned (I thought it had been caught in time) and the third one I havent a clue what is wrong with it, it was spiking and now has hardly any roots left. Basically i am wondering if in two of the cases, should I just give up and how do I save the third one.
Can any one help me? Thanks