Frequently asked
Lake & pond water quality — straight answers
Why blooms come back, what's actually driving them, and how a diagnosis-first approach saves money on the fix.
Which option is right for me?
If you look after one pond or small lake yourself, start with the free satellite read (ponds and lakes about 1 acre and up), then the $179 Pond Health Check: a mail-in kit, 14 lab measurements, and a scientist's call with a diagnosis and a ranked plan. Golf courses, resorts, communities with a chain of ponds, saltwater beaches and coastal canals, and public agencies get a custom program: our team samples on site, and it's scoped on a call and quoted up front. Not sure? Call or email and a scientist will tell you which fits.
How do I order?
Call 573-WATERDX ((573) 928-3739) or email [email protected]. For now every order and quote goes through a scientist first.
Why does my pond or lake keep getting algae even after treatment?
Because algaecide treats the symptom, not the cause. In many ponds and lakes the bottom is the biggest nutrient source: phosphorus that built up over years and recycles back into the water, especially when the bottom runs low on oxygen. If you only treat the water, the bottom keeps feeding the algae and the bloom comes back. WaterDx works out how much comes from the bottom versus runoff from the land around it, so the fix targets the real source.
What is internal loading (and why does it matter)?
Internal loading is nutrients — mainly phosphorus — released from the bottom sediment back into the water. It is often the biggest source in a pond or lake, yet routine water sampling rarely measures it. If the bottom is the main source, runoff-only fixes (like stormwater improvements) won't solve the problem; the fix has to target the bottom. Measuring how much comes from the bottom is the central question WaterDx answers.
How is this different from the lab samples my pond company already takes?
A water sample tells you what the water looked like on the day it was taken. It doesn't tell you why, or whether the bottom is feeding the algae — in our team's peer-reviewed study, one water sample misread what the pond bottom was doing 79% of the time. WaterDx samples the bottom as well as the water, adds your water's satellite and weather history, and weighs the sources, so you get a clear answer on what's driving the problem and a ranked plan, not just another number on a lab sheet.
Does the free satellite read work on my pond?
On ponds and lakes about 1 acre and up. Smaller than that, start with the Pond Health Check.
How long does it take?
The free satellite read is automated, so it arrives by email (and right on the page) a few minutes after you trace your water. It's marked as a preliminary read; a scientist reviews every one afterwards and follows up. A Pond Health Check takes a few days once your sample reaches our lab; then your diagnosis and ranked plan show up in your portal, and a scientist calls you. Custom programs run in phases, starting with a site survey in the first month, and each next step goes ahead only if the results justify it.
What does it cost?
The satellite read is free and needs no account. A Pond Health Check is $179, one-time, for one pond: we mail you a kit, our lab runs 14 measurements on your water, your pond bottom and your algae, and a scientist calls you with a diagnosis and a ranked plan. Pond Monitoring is $299 a year: two checkups a year plus satellite watch and alerts. (The free read can also email you a free monthly satellite check, a good early warning; Pond Monitoring is what adds the lab work and a scientist to find out why.) For freshwater, you can add a toxin test for $89 (microcystin, anatoxin and cylindrospermopsin). Golf courses, resorts, communities with a chain of ponds, saltwater beaches and public agencies get a custom program, scoped on a call and quoted up front. To order, call or email us. The Pond Health Check comes with our guarantee: Clear answer or your money back — if we can't tell you what's driving it, you get your money back.
What if you can't tell me what's wrong?
With the Pond Health Check: Clear answer or your money back — if we can't tell you what's driving it, you get your money back. The full terms are on our guarantee page.
Do you test for algae toxins? Is my pond safe for people and pets?
Algae can make toxins, and you can't tell by looking. For freshwater ponds and lakes, the Pond Health Check has an optional toxin test (+$89) for the three most common cyanotoxins: microcystin, anatoxin and cylindrospermopsin. It's freshwater only. If you see a scum or a bloom, keep people and pets out of the water until you know.
Do you work on salt water?
Yes — fresh and salt. Most bloom fixes were developed for freshwater lakes and often fail in saltwater canals, marinas and beaches: seawater sulfate frees phosphorus held in the sediment, nitrogen rather than phosphorus is often the limit, and copper algaecides harm coral and shellfish larvae. The Pond Health Check measures salinity and nitrogen as well as phosphorus (the toxin test is freshwater only). Saltwater beaches and coastal canals usually get a custom program.
Where do you ship kits, and how do I send the sample back?
Kits ship to the 50 U.S. states, Puerto Rico, the U.S. Virgin Islands and the Caribbean. Outside the U.S. and its territories, pricing is custom — call us. Send it back in the prepaid USPS Priority Mail Express envelope with the ice pack — drop it at any post office or blue USPS box, or book a free USPS pickup.
Are your lab results certified for permits?
Samples are analyzed using standard EPA and APHA (Standard Methods) procedures with documented detection limits and uncertainty. Our lab is not NELAP-accredited; results are for diagnosis and management decisions, not regulatory compliance reporting. If you need certified results for a permit, tell us and we'll route your samples to an accredited lab at cost.
Do I have to fire my pond company?
No. We can work alongside them: we tell you what to ask for and when, and check that it worked. If you're holding their proposal or quote, send it to us for a free second opinion.
Do you sell treatments? Who actually does the fix?
WaterDx guides you through working with vendors, and we take no referral fees. Who does the work depends on the fix. For a Pond Health Check, a vendor you choose does it — your pond company, an aeration installer, a sediment-treatment applicator or an engineer — and we tell you what to ask for and when. In a custom program, our team may carry out the treatment, or we write the specs and work with your vendor. Either way we check that it worked, so you can prove the fix held instead of guessing.
Do you work with HOAs, golf courses, resorts and public agencies?
Yes. Golf courses, resorts, communities with a chain of ponds, saltwater beaches and public agencies are who our custom programs are built for: our team samples on site, maps where the bottom feeds the water, pilots the fix against an untreated control, and monitors to show it worked. A community with a single pond can often start with the Pond Health Check. You don't need any scientific expertise; we turn the diagnosis into a clear decision and a cost.
What causes low oxygen and fish kills in a lake?
Low dissolved oxygen usually comes from too much organic and nutrient load combined with stratification — warm surface water sitting on cold bottom water, so the bottom can't take in fresh oxygen. As oxygen falls, the bottom releases even more phosphorus, which feeds more algae, which use up more oxygen when they die. WaterDx looks at the oxygen record alongside the nutrient sources to find where that cycle starts.
Is WaterDx software, hardware, or a service?
A service — not software you run or hardware you buy. You send us your water (a free read from satellite, or a mail-in kit) and we send back the answer: what's wrong, what to do, and a real scientist on the phone. Bigger water bodies get a custom on-site program, quoted per site.
Is this just AI?
No. The analysis runs on our own models of how ponds, lakes and coastal water work, developed and field-tested over years of our scientists' published research, and calibrated to your water with real measurements. Software and AI handle routine work, like drafting the free satellite read, which is why it costs a fraction of a consulting study. A scientist reviews every result and is the person you talk to.
More detail: The three ways to work with us · Guarantee terms · Free second opinion on a vendor's proposal · Custom programs
Still wondering what's wrong with your water?
One pond? Start with a free satellite read (ponds and lakes 1 acre and up), or get a $179 Pond Health Check: a mail-in kit for your water and your pond bottom, 14 lab measurements, and a scientist's call with a diagnosis and a ranked plan. Bigger or higher-stakes water gets a custom program, quoted per site.
Pond Health Check guarantee: Clear answer or your money back — if we can't tell you what's driving it, you get your money back. Details