In the other container the toms are doing great...

The first thing I would do is examine leaves on the curled plant carefully with a strong magnifying glass. Tightly rolled leaves like that immediately make me suspect aphids or other sap-sucking pests. Some mite species are too small for the naked eye, so a 14x lens is necessary to rule them out.

Second, I would definitely double-check the irrigation line and the moisture levels in the affected container. Dig down a few inches in a few different places in the container with your finger and make sure the soil down here isn't too dry or too moist.

What are the varieties? Is the more affected plant a black variety by chance? Do you prune your plants? If so, did you recently prune them a lot?

Thank you. I pruned the suckers for a while, but not the last few weeks. The soil has the same level of moisture (not dry but not saturated either) than the other troth, according to my cheapo 3-way meter. I'll check on the micro mites. There are a few aphids but not a huge amount.

I wouldn't trust a cheap 3-way meter. I would trust my fingers.

I agree with gorbelly - the curled leaves are definitely showing insect damage. Insects will go for stressed plants, so clearly one of yours is suffering. I suspect, as did gorbelly, that one of the troughs is not getting the irrigation it needs (which is the typical culprit, even more important than fertilizer). I see that you have a good layer of mulch on those beds which helps keep the moisture from evaporating from the soil - is the drip irrigation below that mulch layer? Do the manual-water-meter test which is simply sticking your finger into the soil at least 2 inches to make sure the root zone is moist.

Consider also just removing this tomato plant and buying another start.