What is the issue here? Help ASAP

So I was away at my cottage for the weekend and I think the power went out at some point and the timer didn’t turn the lights back on. No idea when power was lost and for how long the lights were off for. This is what the plant looks like right now.....

Should I keep lights on for a full 12 hours?

The colour definitely is what has me worried

Looks like it could be Iron deficiency. At minimum, it's an immobile nutrient deficiency, because it appears to be happening at the new growth (top of plant) only. Immobile nutrients can't be pulled from older leaves like mobile nutrients can (eg. Nitrogen), so the issue always starts at new growth. Zinc is another possibility, but my initial thought is Iron.

- Medium?
- Nutrients in use?
- Amount of nutrients you're using (and the recommendation amounts of the manufacturer)?
- Temperature?
- Humidity?
- pH of water and water/nutrient mix you're providing the plants?

*Root farm hydro soil and organic worm castings
*root farm nutrients. Base and bloom 10ml of each for every 1 Gal of water
*giving the recommended amount and one tablespoon of blackstrap molasses
* temps 73/75 day 68/70 night
*humidity 50% day 48%night
Ph of 6.2-6.5 always

Could the lights being off for say even a full 24hours have done damage to the plant or the buds?

No, no problem being off for 24.

If the lights were out for more than a few days the plants could start yellowing in the new growth because there wasn't light for photosynthesis to occur but the plants continued to grow. It's more in depth than that but it's a topic all unto itself.

Think of Asparagus. They are green but they can be white through manipulation. To make white asparagus they deprive the asparagus of light. The same thing is done with endive to get the yellow leaves rather than dark green.

Just keep running it at 12/12 like you had been.

Okay thanks guys. I did a feed with some cal mag and a bit more molasses just in case this is possibly iron deficiency. I’m trying to find out from my neighbour when power went out. Such a piss off