I transplanted 37 clones into 4 inch soil containers 13 days ago. 31 of them are thriving very well. However 6 of them (I've named them the "Struggling 6" or "S6") are not growing at all. I'm using Humboldt Mix soil and have watered 4 times in the first 13 days. Lots of water on day 1 (no nutes), again on Day 3 (no nutes) and realized that I over-watered. Used only 1/4 strength nutes on 3rd watering on day 9- giving them 300 ml of water and a 4th watering on day 13 with 1/2 strength nutes and 300 ml of water. Before the most recent watering, the pots were light and leaves were slightly droopy but a beautiful dark green. They all perked up after watering and are looking great. (most are about a foot tall after 13 days). However, the Struggling 6 are not responding or progressing at all. also noted that their pots were still really heavy compared to others so I have to assume that they are not taking water/nutes? They were very lifeless on day 9 before 3rd watering with nutes but perked up by the next day- with the leaves standing up. However there has been no new growth in height at all and no new leaf development. They are clearly runts despite being treated the same as all of the other thriving plants. I've even moved them directly under the light but still nothing. What to do?! Thanks in advance for your help