Scotts Tap Water Substitute is a bluing reagent for histology and cytology staining. It blues hematoxylin gently.

Reagent

• Magnesium sulfate (MgSO4) ---------- 30.0 g
• Sodium bicarbonate ------------------- 2.0 g
• Tap water ------------------------------ 3L
• Mix well

Used as bluing agent for Gill’s hematoxylin H&E staining.