During qPCR of environmental samples (rock biofilm scrapings, and stream sediment), samples are not amplifying appear as a group of curves (send jpeg image). qPCR conditions: Amplification curves for AOA (Arch-amoAF and Arch-amoAR) and AOB (amo1F and amo2R), 40 cycles, 55 degree annealing temp. ABI Fast 7500 machine with Fast Sybr Green Master Mix, 3 second denaturing, 30 second annealing/extension. AOA curve has two standard curves - one with 5 uL of template and one with 1 uL of template. Has anyone seen a similar result?