My plants are bleeding! anyone know whats going on?

my plants are at full height and i need to cut them on top to stop them from growing while the rest catch up before flowering. i feed them with dyna grow growth nutes and dutch master max growth booster. anyway, when i cut my plants they secreted a red liquid. i dont know what this liquid is and i was hoping someone might know. the booster is red colored so it might have dyed the water in the plants water transport chain red. the plants are in foxfarm soil. i did it to the 2 sour grapes that i topped. i havent done it to any of the others because they aren't ready to be tizopped. they are also under some 2700K and some 6500K 100wEq CFLs. thanks for any advice homedawgs



http://i28.photobucket.com/albums/c249/trojanman7/plantblood002.jpg