HYDRO Calcium deficiency?

[NickyChicks]

I have a chocolate kush plant that I think has a calcium deficiency. It's had these tiny little rusty looking spots showing up on it's leaves since about day 10ish, it's now day 22 and they are showing up on the new growth. Using GH trio 1/2 strength, hydroguard, and tap water. pH is 5.9, 647ppm, tent stays between 75°F-63°. Before Sunday it was sharing a reservoir with 3 green crack seedlings and they look fine, so do the other plants that were in a different reservoir same nutrients and water.
From looking on the GWE site I thought calcium deficiency, just wasn't sure if that made sense since my other plants aren't showing the same symptom. Any advice would be greatly appreciated 🙃

[Obi-Wan]

Can you post a picture of the entire plant as well as a picture of the roots? I’m inclined to say they’ll grow out of it but I need to see more evidence before I say that with certainty.

[NickyChicks]

Obi-Wan one of the pics is from Monday before I topped it, I topped it last night. I supplemented Cal-Mag Tuesday night and by last night the pH had risen to 6.6, added pH down last night. 6.3 is what its reading this morning, I read that Calcium could lockout under 6.2. The Roots look healthy IMO and the new grow looks ok.

[Obi-Wan]

I agree, your roots look healthy and the plants look good too. I wouldn’t worry about it. In my experience young plants and pre- harvest plants always show deficiencies. The younger plants just need time to form a mature root system. I generally try to keep my pH in a tight window, 5.8-6.2. Lots of growers suggest allowing it to range the full scale of 5.5-6.5 but I’ve never experienced any issues in the tighter window.

[NickyChicks]

Awesome thanks! I would say for the most part I have been allowing it to range almost full scale between 5.5-6.5, I had kinda been aiming to keep it around 5.8, I read somewhere that some growers say that's a sweet spot for hydro but I suppose that could just be opinion more than fact. Either way, I've been vigilant about checking pH.