In this episode Gale states that he 'cannot account for the color' of the blue meth. However earlier in the show it is established that the blue coloring comes from the fact it is a methylamine preparation, rather than a pseudoephedrine cook. The lab is clearly set up to run a methylamine cook as when Walt runs it it is churning blue meth out without any mention of coloring, If he has ever cooked before from methylamine then it would have been blue according to the lore of the show.
In the Denny's diner, Jesse places his knife and fork down onto his plate to converse with Walter. He picks up only his knife but in the next shot he is holding his fork again.
The hookah on Gale's coffee table is setup incorrectly when his body is first discovered by the neighbors. In the same scene when Victor arrives and inspects the body briefly, the above shot of the room and Gale's body shows the hookah correctly assembled. In the last scene the hookah is also correctly assembled, but the hose is placed differently than it was in the previously mentioned scene, possibly due to the investigation.
When neighbours (and Victor) visit Gale's house, there's a line of blood from the entry wound on Gale's face. It flows back towards his left ear. When the forensics team is in the house, the entry wound and line of blood is missing from Gale's face.
Aside from HF being a poor choice to dissolve a body, the yellow Class 2 "Corrosive" HAZMAT label affixed to the barrel is non-existent. Class 2 HAZMAT are gases.
Since Gale is taller than Jesse, the bullet trajectory could not have traveled downward from Gale's head and hit the teapot.
When Hank is seen browsing the website mineralemporium.com on his bed, the browser shows a saved web page rather than a live website "C:\Users\Mad Props\Desktop\Mineral Emporium screen\ebay hero.html".