Water temperature i believe i think i had that test but try water temperature
If none of the flower colors being bred don't show dominance, it would be pink only because if one showed dominance, than it means you would see that flower and that flower color only. Mixing red with white create pink, and therefore pink would be the only type of flower to have.
The best I have is that the cold air is at the bottom and the warm air is at the top.
