Possible Clues:

• Calcium ---
• That does not sound like a speed for the daytime - too salty
• To get such a lousy speed you need salt (7)
• Egg has to be worth salt
• What a lousy speed to be so salty
• Treat in another way to produce salt
• Saltpeter component
• 'What lousy, little, salty speed! (7)'
• Salt could turn the can up at speed
• Increased payment announced for fertiliser