
Collect 100 mL of water
Fill the amber glass jar almost to the top — about 100 mL (3.5 oz). Leave room for the 1 mL vial of reagent solution you'll add next. Volume matters: your result is reported per 100 mL.
Instructions
Run one water sample at a time. Most of the 30 minutes is just waiting after you add the vial.

Fill the amber glass jar almost to the top — about 100 mL (3.5 oz). Leave room for the 1 mL vial of reagent solution you'll add next. Volume matters: your result is reported per 100 mL.

Add the vial, swirl gently, and wait 15–20 minutes. Two vials? Add the first, swirl, wait 15 min — then the second, swirl, wait 15 more.

Unscrew the holder, set the round filter membrane inside, and screw it back together.

Twist the assembled filter holder onto the syringe tip until it's snug.

Pour the prepared water into the top of the syringe. It holds 60 mL, so you'll fill and push it about twice.

Push the water through right away — don't let it sit. Everything we count is caught on the filter surface.

Unscrew the holder and take out the filter. Keep the side that faced the water pointing up — that's the side we image.

Place the filter inside the imaging box, collection side up.

Set the glass on the box lid — it rests in the square indentation.

Slide the flashlight into the rectangular hole on the top-left of the box.

Open your camera app, rest the phone flat on the box with the lens over the glass, tap the glowing filter to focus, then shoot.
🌙 Turn on Night mode. No exceptions.
Without it, the camera won't pick up the glow and your count will be useless. Takes 5 seconds.
Upload the photo you just took. Our particle counter reads it on the spot — your microplastic count appears right here, and a verified report follows by email within 24 hours.
The box blocks room light and lines up the filter, flashlight, and camera. Microplastics caught on the filter glow under the blue light — those are the particles we count.
Once the box is set up, the app walks you through capturing and counting the particles.
Two tests in your kit? Run one on unfiltered tap water and one after your filter.
Wash the glass or jar thoroughly before drinking from it again.
The Refill 4-pack covers 4 more runs — keep the blue light, syringe, glass slide, and imaging box you already have. $28, free shipping.
Stuck on a step? Use the chat in the bottom-right corner — we reply fast.