Yes, your light is too close. Raise it up to around 30 inches from the seedlings.

Thank you for the feedback. They seemed to do better when the light was higher and when I made sure the plants were dry before watering again. Here's a recent photo. I've started hardening them off outside, but I think I'm going to keep a couple under lights all summer and see how they do and whether I can get some tomatoes and broccoli and peppers.

I have the same exact Mars Hydro 1 light and my seedlings (all kinds) did well at 30 in. However, I moved them all outside when it was time. I'd be interested to hear how the ones you grow inside over the summer do. Good luck!

Going from LED to outside can be brutal because the leaves are way bigger and plants are not heat/UV hardened. I personally don't think the UV is helpful, because it forces you to keep the light way higher than it should be at. So your UV and ideal blue/red LUX height are not the same. I try to aim for about 50,000 LUX which is roughly full sun intensity for LED.

Interesting. I assumed UV LEDS were good. I could take them out of the light.

I dunno. I'm not really sure why they even put UV in some lights. Might have to do with killing bacteria or some weird thing, which...isn't even an issue as far as I know.

The hardening off time for mine grown under these light is almost non existent. I think the UV helps with that.

Good to know. Cool.

"leaves that are curling"

Curling up or down? Down could be a sign of calcium deficiency.

I have the same problem, trying now to use my pepper to make shadow for my new tomatoes grow