super lemon haze deformed new growth/looks like bitten off leaves.. no bugs

the title pretty much says it all. I have one super lemon haze and one kushage and one more sour diesel i got from a buddy from seed. the kushage is really healthy and same with the diesel. the super lemon haze is the fastest grower and healthiest but for some reason the leaves started growing in a little deformed and a couple of them look like they have been half bitten off. i have no bug problems and one 600 watt mh. i give them 6.5 ph water with a quarter strength foxfarm grow big nutes


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only about three weeks old

I have this issue to and would like to know. Anyone?

It just happens. It's not a problem.