Yellow spotting and fading on oldest leaves HELP!

First grow.
Mixed happy frog and ocean forrest 1:1
Temp is at 72. Humidity

A few of her bottom leaves have a little yellow spotting and fading at the tips.
Its only on the oldest leaves in the undergrowth. What could it be?
She seems pretty healthy other than that. Could it be the humidity is 62% during day and 70 at night... I cant seem to lower it.

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Right now shes about 6 inches from the scrog and 15 inches from the light.
Ive been feeding her a gallon of water every 3 days steadily. Recently started feeding b-52 as well.
Could I start including molasses in my feeding? Haven't heard of any benefits of it in veg.

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All her tops seem lush green and healthy.

Heres some pics with regular lighting.
These are her oldest leaves. I want to stop the problem now before it gets worse.
Could it be calcium or mag?
Gonna be feeding her just water for feedings until i get a reply.

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IMO- it looks like a Calcium Deficiency.

Good Luck on Your Grow

Doesn't look deficient in anything to me so just keep watering. Scope your damaged fan leaves front and back to check for tiny pests. Otherwise you are probably good. Bottom fan leaves typically start to look a little rough when they start losing light and they are more prone to getting nutrients splashed on them which is another possibility.

Im thinking its calcium as well. I noticed one of the top growths leaves had a few yellow dark small spots on it.
Should I pick up some calmag and feed with water only? Should I hold off on the b52 till flowering?
I will be using big bud, nirvana and overdrive in flower.