THE WATER TESTStep 1 of 12
Filling the amber glass jar with water at the faucet
Step 11 min

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.

Adding the reagent vial to the amber glass jar with a dropper
Step 215–20 min wait

Add the vial and wait

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.

Step 31 min

Put the filter in the holder

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

Open the holder, drop the filter in, twist it shut

Step 41 min

Attach the holder to the syringe

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

Twist the holder onto the syringe tip until snug

Pouring prepared water into the top of the syringe
Step 51 min

Fill the syringe

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

Pushing a water sample through the syringe filter
Step 6Right away

Push the water through

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

Unscrewing the filter holder to retrieve the filter membrane
Step 71 min

Retrieve the filter

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

Setting the round filter into the square window of the imaging box
Step 81 min

Put the filter in the imaging box

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

Setting the orange glass square over the window on top of the imaging box
Step 91 min

Put the glass on the lid

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

Sliding the flashlight into the rectangular hole on the top-left of the box
Step 101 min

Add the flashlight

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

A phone resting on top of the imaging box with its camera app open, showing the glowing filter
Step 111 min

Take the photo

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.

Step 121 min

Upload your photo

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.

Swipe or tap the arrows to continue

How the imaging box works

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.

Then count it in the app

Once the box is set up, the app walks you through capturing and counting the particles.

Compare two sources

Two tests in your kit? Run one on unfiltered tap water and one after your filter.

When you're done

Wash the glass or jar thoroughly before drinking from it again.

Want to test 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.

Refill 4-pack — $28

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