If you are using tap water its probably the chlorine in the water. Thats what usually happens. Its ok. Its not going to die. It could be from over heating. What kind of light are you using? I feed my plants basically one week after rooting. It needs to be half strength or less. If your not sure then use 1/4 strength at first. Its better to be safe than sorry. What kind of fertilizer are you going to use? And what do you not uderstand about parts per million? Its the amount of salts that are in the solution.

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