Down the channel until it seats
Slide the flashlight down the angled channel, head first, until it seats against the round housing. The channel sets the angle, so there's nothing to aim.
Low batteries make a real sample read as clean, and the beam still looks fine when they're low. If it worked before and then stopped, swap them.
Unwrap the digital microscope and press the power button. Drop it into the round housing, screen up, so the lens looks down at the light. Leave the wand aside until you have a filter to read.
Fill the jar almost to the top with the water you're testing. It holds about 100 mL (3.5 oz). Leave room for the 1 mL vial you add next. Results are reported per 100 mL, so use the full jar.
Add the vial, swirl gently, and wait 15–20 minutes. Longer is better; the dye needs time to bind.
Cover the jar while you wait. Dust from the air lands in an open jar and gets counted.
Open the holder, drop the filter in, twist it shut
Unscrew the holder, set the round filter membrane inside, and screw it back together.
Twist the holder onto the syringe tip until snug
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.
Older kits shipped a 100 mL vial, which went through in one pass. The kit now ships a 60 mL syringe, so a 100 mL sample takes two pushes: fill, push, fill again, push the rest. Keep going until the jar is empty. It all goes through the same filter.
Unscrew the filter holder before you pull the plunger back for the second fill. Pulling against the filter can damage it.
Push the water through right away; don't let it sit.
Unscrew the holder and take out the filter. Keep the side that faced the water pointing up. That's the side you read.
With the tweezers, lay the filter flat on the wand, collection side up. Slide the wand into the rig until the filter sits under the microscope and over the light. A curled disc throws shadows that read as empty filter, so get it flat.
Dab the filter with a paper towel until slightly damp. Damp lies flat; bone-dry curls.
Move the wand around under the microscope to hunt for microplastic particles
Switch on the microscope. The lens sees a small patch at a time and the particles are scattered, so move the wand in and out and side to side until you have covered the whole disc. Go slow and overlap your passes.
Each faint glowing dot or short fiber is a suspected microplastic. Count them as you go. The color varies with the lens and the light — more red or less red is fine. Compare against the examples below.
Your count is a floor. The membrane is 1 µm, so anything smaller passes straight through, and some of what lands is too small to resolve. For every particle you can see, there are more you can't.
Instructions
One sample at a time. Most of the 30 minutes is waiting after you add the vial.
Three parts. Tap one to open it.
Slide the flashlight down the angled channel, head first, until it seats against the round housing. The channel sets the angle, so there's nothing to aim.
Low batteries make a real sample read as clean, and the beam still looks fine when they're low. If it worked before and then stopped, swap them.
Unwrap the digital microscope and press the power button. Drop it into the round housing, screen up, so the lens looks down at the light. Leave the wand aside until you have a filter to read.
Fill the jar almost to the top with the water you're testing. It holds about 100 mL (3.5 oz). Leave room for the 1 mL vial you add next. Results are reported per 100 mL, so use the full jar.
Add the vial, swirl gently, and wait 15–20 minutes. Longer is better; the dye needs time to bind.
Cover the jar while you wait. Dust from the air lands in an open jar and gets counted.
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.
Older kits shipped a 100 mL vial, which went through in one pass. The kit now ships a 60 mL syringe, so a 100 mL sample takes two pushes: fill, push, fill again, push the rest. Keep going until the jar is empty. It all goes through the same filter.
Unscrew the filter holder before you pull the plunger back for the second fill. Pulling against the filter can damage it.
Push the water through right away; don't let it sit.
Unscrew the holder and take out the filter. Keep the side that faced the water pointing up. That's the side you read.
With the tweezers, lay the filter flat on the wand, collection side up. Slide the wand into the rig until the filter sits under the microscope and over the light. A curled disc throws shadows that read as empty filter, so get it flat.
Dab the filter with a paper towel until slightly damp. Damp lies flat; bone-dry curls.
Switch on the microscope. The lens sees a small patch at a time and the particles are scattered, so move the wand in and out and side to side until you have covered the whole disc. Go slow and overlap your passes.
Each faint glowing dot or short fiber is a suspected microplastic. Count them as you go. The color varies with the lens and the light — more red or less red is fine. Compare against the examples below.
Your count is a floor. The membrane is 1 µm, so anything smaller passes straight through, and some of what lands is too small to resolve. For every particle you can see, there are more you can't.
Both of these make a sample with plastic in it look clean. If your screen suddenly shows nothing, check these before you trust the result.
The most common reason a real sample reads as clean: the 25 mm filter disc is curled. If it curls or buckles, the light hits it unevenly and you get dark patches of shadow that look like empty filter. Handle it with the tweezers and get it lying flat before you read it.
Dab it with a paper towel until slightly damp. Damp makes the disc stick flat; bone-dry, it curls.
The flashlight is fixed in place, so aiming isn't the problem — the batteries are. Below about 50–70% charge the blue light stops exciting the dye and nothing glows, even with plastic on the filter. You won't see it happen: a half-dead cell still throws a beam that looks bright. If the kit was finding particles and then stopped, put in fresh batteries before you trust a clean result.
A quick tour of the kit and how the imaging works. Your kit might look slightly different from the video as we keep improving the product.
A real 100 mL sample of bottled water, start to finish: add the dye, check the blank filter, push the water through, and count what glows. Watch the blank check at 0:40 — look at the filter before any water runs through it, count anything already glowing, and subtract that from your final number.
Have two tests? Run one on unfiltered tap water and one after your filter.
Wash the jar thoroughly. Don't drink from it.
You read the result yourself, moving the wand under the microscope. Each one shows up as a small, faint glowing dot. Use these as a reference, then count what you see.
The color varies with the lens and the light: deep red, warm orange, or almost blue. Every view below counts.
What you're looking at
A long fiber may be polyester, or it may be cotton or rayon, which aren't plastics, or a clothing fiber that landed from the air while your sample sat open.
Carbon shed by a carbon filter, grit, rust and other debris all look like black specks at 10x, the same as black plastic. Looking at one doesn't tell you which it is. More on this.
These images do not show any microplastics. An even view with no distinct glowing dots — nothing to count.
Each refill covers one more run — keep the microscope, syringe, and filter holder you already have. sold separately.
Stuck on a step? Use the chat in the bottom-right corner.
Don't have a kit yet? The microplastics test kit is available by request. Tests are sold separately.