Everybody will have a different answer for you.... but you know what? Just like the name implies MJ is 'weed'. It will surprise you under what conditions and soil they will grow from.

My advice would be going back to the basics. Get some potting soil from Lowe's or Home Depot, and don't add anything. You will be surprised how well it will grow without any of the additives people are suggesting to you. Get a few growths under your belt before you experiment with any fancy additives.

My opinion on your situation? I think they are not healthy because you probably have too much 'crap' additives in your pots. Well, maybe not crap, but there is such a thing as overfeeding and killing your plants with what you think is needed, and its not. If you wanted to grow tomatoes in your garden, would you buy all the crap you've put in your MJ pots? Probably not!
I say just use good potting soil and get a few crops under your belt, and only after a few successful harvests should you use ANY additives, and start in very small amounts until you see that its helping or not.

What kind of light are you using? ....and what kind of temperatures are the plants in?

SpaceNeedle