Black blotches on clones

Hi i have 5 clones growing in rockwool that are currently 11 days old.
Im unsure of the plant strain as it was cut from a friends plant and in my opinion he cut them too short only about 1 node down. I used clonex for my rooting hormone only and no other stimulants. My clones are kept under twin cool white 4000k fluros 24/0, they are watered(misting the leaves, spraying the dome and making sure my cubes are at least damp) 2 times per day using filtered tap water. visual inspection of cubes on the exterior has no root growth yet, but upon carefully prying open a cube for inspection, roots are starting to form anywhere between 3 - 6ml.

Now my problem is that a lot of the leaves are turning yellow which im hoping is just the clone using it's stored nutrients for root growth, but the yellow leaves are also producing black blotches over them and also some of the green leaves, which is my main concern.

The yellow leaves are starting to feel to have a bit more of a crisp feel to them rather than a smoother texture of the healthier leaves, also some of the healthier green leaves are starting to curl and die on the tips.

So im worried if this maybe a fungus thing, or phosphurus thing maybe(sorry for my ignorance if i dont know what im talking about there) but im really worried as i really want to keep these puppys alive!

I have enclosed pictures for diagnosis if possible.

Thanks for your time in reading my post.
bez

I think you have several problem going on here. You will need to post all the details. What kind of water are you using, what kind of method are you using, what kind of ferts, what is ph an ppm levels?

The black splotches are likely 1 of 2 things. You mentioned misting water on the leaves, I would stop that. The water you might be using is leaving droplets on the leaves and depending on how low your lights are, may be burning the leaves and causing the splotches. The other likely culprit is that you are using RO water, distilled water or spring water. Your water is short on needed minerals mainly calcium and magnesium. There is a product called cal-mag that you need to use when using anything other then tap water. I mix my water 50/50 with RO and tap to give me a good mix.

The yellowing is likely due to insufficient nutrients. I have never heard of a leaf yellowing so that it can focus on root growth. Believe me, a plant can handle both root growth and leaf growth.

The crisping of leaves is likely due to insufficient watering. Again you should post every detail of your system and method so that we can identify where you are falling short.

Hey mate, thanks for the reply. i took your info on board straight away. I stopped misting my leaves, used 50% normal tap water / 50% filtered tap water with a very light nutrient solution and just watered the cubes themselves.

And wow what a turn around, in only 24hrs my clones have recovered awesomly, they a standing upright with no wilt and to my suprise 2 of the clones have produced roots protruding through the rockwool .. yeah so it's been great thanks to your advice.

And sorry i didnt put in enough info in my first post, i will remember next time to add as much info as possible.

thanks again mate, cheers

Hi There im having the same problems 12 days old and just realized im using soda water that i use for my mother AND even worse left my top vent open too much and the rock wool has dryed out now im using rain water and bought a heated dome 20 quid and its not high enough in my opinion think i will go back to my tent which is bout 12 inchs high , miy dome is bout 8 incs high hate being a beginer but will see it through