Week 5 flower Light on temp high 70s light off temps high 60s, is it to early for leaves to be changing colors feeding beastie bloom fishsht

Yellow leaf tips and purple coloration are often associated with excess nutrients. Based on how your plants look I would continue what you are doing though. A little nutrient stress is ok. If it gets worse then I'd back off a little. If I'm not mistaken purple coloration comes from excess phosphorus sometimes. Cold temps can also cause it too though. Light stress can too but you usually see that more on the stems first.