July 22, 2026

This summer's article will cover a simple procedure to verify that a water medicator is drawing and dosing at the intended rate. A medicator should be tested before administering medication, vaccine, supplements, sanitizer, or any other water-soluble product through the drinking water system. Verifying the dosing rate helps prevent under-dosing, over-dosing, wasted product, and inconsistent delivery in our barns. 

Preparation

  • Use clean water for the test unless the manufacturer recommends another method 
  • Do not allow test water or product solution to reach animals unless it is intended for treatment 
  • If the medicator fails the test, do not use it for treatment until the cause has been corrected and the unit passes a follow-up check 
What We'll Cover:
  • Importance of Accurate Dosing
  • How to Verify Your Medicator
  • Calculating Correct Draw Rates
  • Troubleshooting & Best Practices
Tools:
  • Clean measuring cup or graduated container marked in ounces 
  • Clean bucket or pail large enough to collect discharge water (5-gallon bucket) 
  • Clean water for the test 
  • Calculator 

Basic Dosing Check Method

  1. Know what the current ratio setting of the medicator is supposed to be.

  2. Inspect the unit for leaks, cracked fittings, loose clamps, cloudy or kinked suction tubing, plugged strainers, worn seals, or buildup around the intake components.

  3. Turn off the water to the barn or bypass the medicator during preparation.

  4. Disconnect or isolate the medicator from the line leading into the barn so you can collect the water that comes out of it.

  5. Fill a measuring cup with a known amount of clean water to act as the test stock solution.

    1. Tip: When I do this, I like to fill the measuring cup up to 8 oz and let the medicator pull out 4 oz or 5 oz of water.

  6. Place and hold the suction tube in the measuring cup.

  7. Place a bucket under the medicator discharge hose.

  8. Turn on the water slowly so water flows through the medicator at a normal operating rate.

  9. Allow the medicator to draw the measured test water out of the measuring cup while collecting water in the bucket.

  10. Compare the amount of test water drawn to the amount of water collected.

Example Check at 1:128

If the medicator is set at 1:128, it should draw approximately 1 ounce of stock solution for every 1 gallon of water that passes through the unit. 

To check this setting, place 8 oz of clean water in the measuring cup and collect water in a 5-gallon bucket. When the 5-gallon bucket is full, 5 oz in the measuring cup should be gone. Compare the amount of water left in the measuring cup to what you were expecting to use. 

If more than 5 oz of water was used, the medicator is over-dosing. If less than 5 oz of water is used, the medicator is under-dosing. 

Use the ratio setting to determine the expected draw volume. 

Keep units consistent. 

For a ratio written as 1:X (ex: 1:128), divide the volume of discharge water by X to estimate the amount of stock solution that should be drawn. 

For example, at 1:128, 640 oz of discharge water divided by 128 equals 5 oz of stock solution. 

Ratio Setting per Expected Stock Solution
Ratio Setting Discharge Water Collected Expected Stock Solution Draw
1:128 5 gallons (640 oz) 5 oz
1:100 5 gallons (640 oz) 6.4 oz
1:64 5 gallons (640 oz) 10 oz
Troubleshooting if the Medicator is Not Accurate
  • Low or inconsistent draw: Check for a plugged strainer, cracked suction tube, air leak, worn seal, clogged pickup, or insufficient water flow 
  • Over-dosing: Confirm the ratio setting, check for incorrect adjustment, and verify that the unit is assembled correctly 
  • Loss of prime: Inspect the suction hose, foot valve, clamps, and fittings for leaks or restrictions 
  • Leaks or dripping: Tighten fittings, replace worn seals, and inspect the body for damage 
  • Scale, sediment, or biofilm: Clean intake parts, strainers, and tubing. Consider whether water quality is contributing to buildup 
  • Pressure or flow swings: Test the unit under normal barn operating conditions and avoid shared water demand changes during the check 

Final Thoughts

Without checking the accuracy of our medicators, we don’t know if the birds are getting the correct dose of the product we’re trying to give them. Products go through testing to figure out the ideal dose to support our flocks. 

If we are under-dosing or over-dosing, we could be causing more harm than the help we’re trying to provide. It’s also important to mix medications and chemicals at the manufacturer’s labeled rate. 

If you have questions or want help testing medicators, reach out to your BVS representative—we’re always happy to help.

Continue reading more articles in BVS Poultry Talk today!

 

 

For More Information:

Samantha Shirk, Marketing Manager, Best Veterinary Solutions

marketing@bestvetsolutions.com

515-827-0105

« Back