Somewhat sadly, fungicides are mostly preventative. They don't kill fungus once it is established. Gurney's First Start™ Seed Starter is sterile. The ProMix stuff is peat-based, and I think it is intentionally not sterilized, but pretty certain not to be fungally infected. So I suspect that's not the problem. The fact that you have some experience doing seed starting makes this especially strange. I assume that you've kept control of the temperatures. 5 week old seedlings need fertilization. What have you used?

Yes and no. First the excess nitrogen needs to be removed and this may sound strange to you but you should feed the microbes sawdust, ground up twigs or cardboard. Feeding the microbes a diet low in nitrogen and high in carbon will force the microbes to consume excess nitrogen in the soil to live. The microbes main diet is carbon and nitrogen at a ratio of 24 parts carbon to 1 part nitrogen and the items I mentioned have a ratio of 378 parts carbon to 1 part nitrogen for cardboard and up to 500 to 1 for twigs and sawdust. They eat the carbon and turn to the excess nitrogen in the soil to eat, problem fixed. So get about a 1/2 cup of ground up cardboard, twigs or sawdust and mix into the soil. (you figure out how to grind them up) After a couple of weeks it's time to start feeding the plants again but only with the fish stuff DON'T use the Trifecta! It was a one time application only. Fish emulsion has a 5-1-1 nutrient ratio and right now your plant needs MORE potassium than nitrogen the fish stuff doesn't have, so 1/2 of a dried banana peel will do every two weeks. Fish emulsion has 3 to 5 parts carbon to 1 part nitrogen so when consumed by the microbes they leave a lot of nitrogen for the plant to use. Adding any other source of nitrogen will be too much. But if you really want to make the plant healthy and happy get some alfalfa meal, it's rich in everything a tomato plants needs that the fish stuff doesn't. Cut the fish stuff in half and cut the alfalfa meal recommendations in half and you will never have a nutrient problem suffered by many who use pots to grow in. The plant that has already grown will never produce a flower or tomato and flowers will only appear on new growth so don't worry, and cutting off the bottom leaves didn't hurt it a bit. To be honest I never read your original post so I didn't know you mentioned no flowers, All I looked at was the picture.

If somebody can tell me what I’m doing wrong that would be great. One of my cayenne pepper plants, pepper ends, are shriveling. The other plants are fine and are not doing this. The entire plant looks healthy, the leaves are perfect the stocks look good, there are no signs of wilting or discoloring. I am a beginning gardener. SOS

Aaarrrgggg. That’s what I was afraid of. I’m actually in San Antonio, Texas and this is the first time I’ve ever tried to grow anything. My parents live a bit south of me and have been very helpful with suggestions. (I come from a long line of Aggies, so I’ve got lots of advice!) I think if we plant them in mid-September, as long as we can get some “good growth,” we should be able to have some cucumbers before the first frost. Not sure if that’s true, though. So I should probably dig this plant up? It’s growing next to two tomato plants that seem to be doing quite well, with no signs of Aphids.