Noob Here! 2 Week Old Plants - Lime Green Leaves, Slow Growth? Problems, Please Help!

This is my first grow. I'm a medicinal patient with legal authorization to grow.
I have 4 Plushberry (Indica Dominant) plants that sprouted exactly 15 days ago. All of them have been treated equally but it seems they all have some issues.
Over the last few days the two larger ones have started to turn lime green.
The other two are shorter (one is super short and low to the ground) and growing really slowly. I'm trying to figure out why.

The plant on the left had the seed caught on it's first set of leaves and made them twisted and bumpy. I had to remove it with a pair of tweezers during the first week.

My question is. What's going on? Does the lime green mean that they want their first dose of 1/4 strength nutrients?



They've been under a TaoTronics TT-GL14 240w LED in a 3x2 grow tent. The light is about 18 inches from the plants.
18/6 light schedule.

Fox Farms Ocean Forest soil with added chunky perlite. 25-45% humidity. Daytime temps 78-82 degrees. Nighttime temps 65-70 degrees.

8 inch clip fan giving them a slight breeze 24 hours a day. There's no exhaust or outtake fan on the tent, but the vents and 6 inch holes are all opened up when the lights are on. The tent is in a large room.

I haven't been able to test the PH of my water yet. I just ordered a PH meter and it will arrive any day now. But I do have a TDS meter.
The water I'm feeding them is filtered/purified (25ppm reading with my TDS meter) and at room temperature.
I've been watering them every other day or when the soil is dusty dry an inch or so down and the cups feel light.

Haven't fed them any nutrients yet, but I have the General Hydroponics Flora Series ready to use when the time is right.

Also... I recently ordered an Area 51 XGS-190 LED to replace my current light. It will arrive this upcoming week. These plants will go under it once I get it.

Any help would be awesome!!
Thank you!!!!!!!

When plants are this small they show a different sign when overwatered. Yours looks like the classic overwatering signs with the wavy leaves and yellowing of bottom leaves. You have enough food in the soil because it's lush green on your top growth spurt. Feed with water and lay off the watering cycle. I would lift up the cups to sense if theirs water weight in those cups before I feed them. If you like your water cycle and like to keep to it, add more perlite the next time. I suggest a 50% ratio of perlite to soil.

I've been watering with a spray bottle. I haven't ever seen run-off come from the holes on the bottom of the cups. There is a 1 inch layer of 100% perlite at the bottom.

Today I woke up and the 4th plant looks like it's taking a turn for the worse. It's extra droopy and appears to be on its way to death. The last time I watered it was 2 1/2 days ago but the cup feels lightweight and super dry! I guess I'll hold off on watering it for another day. I think I will ditch the spray bottle and pour water evenly in the soil until I see some runoff?

i will post a picture soon.
thanks

Here is the 4th plant. Looks bad I'm sad...

It is sad looking but I really think it's an overwatering issue. I think you should mix the perlite with the soil the next time. If you wanted more air to get in the pot than buy one of those pots with a bunch of holes on the side, it'll work better than adding perlite at the bottom. By doing that you can also feed through the bottom and make water wick to the top.

I added and mixed about 20% perlite with the soil when I first planted them. I guess I need more next time.