Personally, I don't think the nighttime temperature is playing a role, as they can come from areas that rarely get as "cool" as 25°C.
The most common non-flowering reasons are lack of light (that doesn't seem to apply), lack of nutrition, but the sheer number of nice, tight growths suggest that's not an issue, and as Dorothy said, too much nitrogen.
Tell us about your feeding regimen - how frequently, what formula, and at what mixing ratio.
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