Bruce Banner #3 Autoflower

Hello all, this is my 2nd indoor grow and my first attempt with autoflowers. I'm using amended soil, (promix,cow manure, worm castings, organic compost,perlite and vermiculite) in 4 gal cloth pots. Germinated 4 Bruce Banner #3 autoflowers, using wet paper towel method, all 4 cracked. Seedlings are under a 3 bulb t-5 HO fixture for two weeks in small pots. will transplant into 4 gallon pots at end of second week. So far 3 out of four look great, the four one is a little bit stunted.