Actually, they don't look all that bad to me. They sure don't appear to be dying. Their lime green color (is that valid or just the photo?) is somewhat anemic looking but that could just be from excessive watering. Peppers don't care to be always wet.

Edge burning of leaves can have several causes - sunburn, excessive nitrogen, root rot from too much water, etc. So we need more info please.

They appear to be in a container, correct? 3 plants in one container? How old? Inside or outside? What is the growing medium? Feeding them what? How often? Watering schedule?

Dave

They're in a 3-gallon container, about a month old, inside with a seed starting/potting soil mix.i'm not sure what exactly is in it but the soil does hold water pretty well.

They're growing under over-driven t8 fluoro's which are putting our around 30,000 lumens (i've tested it under a light meter) which should be plenty to grow.

I haven't fertilized them at all yet since I only transplanted them a few weeks ago and with all the new soil I figured it would have enough nutrients. (I've also tested the soil which says there's plenty of nutrients left.).

The watering might be the problem, i've only watered them about 3 times, or about once a week in the past 3 to 4 weeks. They were all heavy waterings and the pot seems to retain water well.

Could I have a drainage problem, and if so what should I do? Would aerating the container by poking holes with a chopstick help get some oxygen into the soil and some moisture out?

Hi,
I believe you've got them it too big of a pot for their size. There's no roots to suck up all the extra moisture. The moisture is not going to dissipate any time soon even if you put more holes in. If it was outdoors in mid summer the soil might dry out fast, but not now. Anyway, you need to re-pot them into a smaller container for now.
Remy

I don't see any permanent issue with those seedlings. We can all speculate on what is g[r]o[w]ing wrong, but the photo doesn't show any serious problem.

Based on your info then my best guess would be a watering/soil drainage issue. Transplanting them to individual pots with a well draining soil-less mix (with or without some fertilizer) and reducing the amount of watering should resolve that issue.

Peppers prefer to dry out between waterings as the roots need oxygen even more than they need water. Once adjusted to their new containers, a mild 1/2 strength feeding would be of help. You don't indicate where you live so I can't judge how soon they can be transplanted to the outside but I think you'll see them perk up once that happens.

Hope this helps. :)

Dave