How to use the STS SPRAY - Dry kit - Makes 2L

Your Kit Includes

Silver Nitrate

Sodium Thiosulfate

Tools and Materials You Will Need

Inculuded

  • Part A Powder/Crystals - Black Bag
  • Part B Clear Crystals - Clear Bag

DIY Materials Needed

  • Distilled or Reverse Osmosis Water
  • 2 8oz Brown Glass Bottles (Two beer cups that are clean will work)
  • 32oz Brown Glass Bottle w/Black Sprayer Top(LIght proof Sprayer, or store in dark when not in use)
  • 33 Gallon Black Trash Bag
  • Tape
  • 60 cc/ml Syringe
  • A Cool Dark Place for Storage (Fridge)
  • Nitrile Gloves(please use these)
  • 500ml/2 Cup Glass Mixing Container
  • Small wire whisk
  • Safety Goggles

Basic Safety Recommendations
The following steps require careful measuring, along with basic chemical safety. It is strongly recommended you work on a flat surface with a plastic sheet or several layers of newspaper to protect it. Silver nitrate does stain brown to black, so gloves and safety goggles are recommended.
Sodium thiosulfate has a very low toxicity, make sure you still wash up any spills well to remove all concern. Both of these solutions can be safely rinsed down the drain, when followed by a large amount of water.

Measuring and Mixing Stock Solution "A"

  • Fill your 500ml measuring cup with 125ml of distilled water
  • Mix the black bag's contents into the 125ml of distilled water
  • Pour the solution into a brown glass bottle and seal tightly
  • Label the bottle "A" 
  • Thoroughly clean the 500ml container and rinse with distilled water

Measuring and Mixing Stock Solution "B"

  • Fill the 500ml container with 125ml of distilled water
  • Mix the white crystals from one of the clear bags with the 125ml of distilled water
  • Pour into the brown glass bottle and seal it tightly
  • Label the bottle "B" Sodium Thiosulfate
  • Thoroughly clean the 500ml container and rinse with distilled water

Keep Both "A" and "B" Solutions Cool and Dark! Preferably in the Fridge.

Mixing and Diluting STS
The next step is to mix the two stock solutions together properly, creating the actual Silver Thiosulfate Solution (STS).
Before using the STS, it must be diluted to a weak solution for spraying!

  • Measure 50ml of stock solution "B" with the 60cc syringe and gently squirt it in the 500ml glass measure
  • Thoroughly rinse the syringe with distilled water, or change to a new syringe
  • Measure 50ml of stock solution "A" with the 60cc syringe
  • While whisking solution "B" in the glass measure, slowly squirt solution "A" into the glass measure in less than 30 seconds
  • Pour the mixed solution into the 32oz brown glass bottle with black sprayer top
  • Add 900ml of distilled water to fill the sprayer the rest of the way.
  • Test spray on a leaf to if solution still beads up and rolls off.
  • You now have a sprayer bottle with a 1:9 dilution of STS and water. You want to do your best to protect it from light and heat.