I'm not sure what you are using for a light but you might want to get a more powerful one. Those plants should be a lot bigger and fuller. I'm growing the same exact strain under about 150watts of led. And it's 5 times the size of yours. And I'm only using General Hydroponics basic nutrients and cal mag. I did top my plants once. And I can see you didn't. But still, there is no reason why your plants shouldnt be at least 3 to 4 times bigger, even without topping.The Runtz 13 and pineapple are really good yielders.
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