Weak stems. Unsure of the problem
This year I started a hydroponics system. I'm still a complete novice and don't really know what I'm doing. About a couple of months ago I started some seedlings in peat pellets and about a month or so ago I transplanted the seedlings into the system. The system I went with is a recirculating DWC. I also transplanted some plants that were growing in dirt into the system. Well, it seems there is a problem. The dirt plants are doing good and have gotten much bigger since I've transplanted them. Some, however, appear to have weak stems and are leaning over a little. The seedlings are doing the same. They all seem to be growing just fine, but they aren't perky and standing up straight like they probably should be. The leaves and stems have a nice green color, not pail, yellow or anything of that sort. What could be causing the stems to be weak and leaning over?
I have a light thats set at 400 right now and cycle is 18/6, if any of this helps.
Any help is very much appreciated!