Hey IceGrower! I agree with what was previously posted here.
It is way to hot for your Seedling, also u overfed and overwatered them heavily.
Just let em grow out..do not flush the medium with 10 Liters of water at this stage of the plant, even if you have overfertilized as it will drown the roots to death.
Also i cannot see any Perlite in that soil, maybe the soil is too muddy and it holds water for too long so the roots are drowned and cannot breath. This will make the problem worse rather than make it better.
Just let it grow out, give them only plain water or start with a new seed and soil, the plant is still so small now that you would not loose much time when you start over