I have 3 seedlings in 8:1 Sphagnum peat to perlite mix. Two of them are G13 Pure Power and 1 is GHS The Church. The Church's first leaves don't look all that good and compared to the Pure Power this seedling is way behind in overall growth Here's a link to my grow journal which has all the details of my environment and the pics: http://forum.grasscity.com/indoor-g...il-ghs-church-g13-pure-power-white-widow.html
My suggestion would be to add more perlite to your mix. The Sphagnum peat can cause some serious spikes in PH. With that ratio in your mix, you only need to water once...maybe twice a week. That looks like what is happening with the church plant....hot soil and too much moisture.
I had these cups in bags to keep humidity up, and if you look close you can see the same type of yellowing on the pure power....they just handled the high moisture a little better I guess. I've had these going for 2 weeks, we've had 2 waterings in that time, 1 was day before yesterday. I'm jus trying to get these a little bigger, maybe 1 week to 10 more days in the cup, before transplanting to FFOF. Hopefully the GHS seedling plays a little catch up, I don't want to burn it with the FFOF.
Ok, 6 days later and here's what I have. Below are pics of 1) G13 Pure Power planted same day as "The Church" and sprouted within 24 hours of each other, 2) GHS "The Church" at the same distance. 3) Macro of retarded GHS "The Church" Pure Power: GHS "The Church" Size comparison: Macro of deformed GHS "The Church":