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Strong light, strong nutes, etc, are all things that are a bit like a massive workout to build up a bodybuilder. Clones are much too weak for that. They want soft light and soft conditions.

The old growth on your clones will never look good, just concentrate on the new growth and check how thats doing.
Your new growth looks fine to me.
Just be really gentle with light and nutes until you can see that they're beginning to look strong.

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