So, here is my opinion. Sounds like you are giving up on this grow. Why not experiment? Take a handful of plants and give the 25% nutes. Do another group with 50%. See what happens!! Also, what is the ph of your distilled water? I have checked before and found it high, around 7ph. That’s to high and will also cause problems.
We have all killed seedlings. I killed a LOT starting out. It’s how you learn. Don’t get discouraged!!