Water Testing Guidelines
You cannot fix water you have not measured. Every treatment system on this site solves one specific problem, and the wrong system will not fix your water no matter what it cost.
A lab test costs a fraction of a filtration system and tells you exactly what you are dealing with.
Send us the results and we will tell you what you need, including if the answer is nothing.
We size the system off your actual numbers rather than off a symptom, and we are the ones who install and service it afterwards. That is a very different thing to guessing.
The short version
R J Hill Laboratories in Hamilton. Routine Water, plus silica, plus E. coli on any tank, roof, surface or shallow bore supply.
Run the water for 20 minutes first, and sample as close to the source as possible, ahead of any existing treatment.
Email the certificate to contact@pumpstuff.co.nz with your water source and how many people are in the house.
What test to ask for
We recommend R J Hill Laboratories in Hamilton. Ask for:
Routine Water (RW)
The standard suite for a private supply. It covers pH, alkalinity, hardness, turbidity, conductivity and dissolved salts, plus iron, manganese, calcium, magnesium, sodium, potassium, copper, zinc, lead, arsenic, boron, chloride, sulphate and nitrate.
Silica
Tick this as well. It is not in the routine suite and it is the usual culprit behind white smears on glass that will not come off. There is no threshold to hit, we just need to know whether it is in your water at all.
E. coli
Add it on any tank, roof, surface or shallow bore supply. Read the caveat below before you rely on it.
Hill Labs are on 0508 HILL LAB. They will send you sample bottles and instructions.
How to take the sample
A bad sample gives you a confident, wrong answer. The first two steps matter more than anything else.
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Run the water for 20 minutes first
Water that has been sitting in the pipes overnight is a test of your plumbing, not your supply. Copper, zinc and lead readings in particular go up the longer water sits against the pipe.
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Sample as close to the source as possible
The bore head or the tank outlet, ahead of any existing treatment. If you sample after a filter you are testing the filter.
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Fill the bottle to the top and cap it straight away
Keep it cool from that point on.
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Get it to the lab quickly
E. coli in particular has a short holding time, so post it early in the week rather than on a Friday.
Bore water and iron: watch what comes out of the tap
This one is worth doing before you even order a test, and it tells us which kind of iron problem you have.
Run a glass of water and look at it immediately, then look again after ten minutes.
Clear out of the tap, then goes cloudy or orange as it sits
Dissolved iron, ferrous
It is invisible in the ground because there is no oxygen down there, and it drops out as rust once it meets air.
This is the common one, and it is what the oxidising systems are built for.
Brown, orange or cloudy straight out of the tap
Iron already out of solution, ferric, or iron bacteria
That changes the treatment: it needs filtering rather than oxidising.
If there is a rusty slime or a rotten egg smell as well, the bore itself likely needs cleaning before any filter will keep up.
Tell us which of those you are seeing. It genuinely changes what we would quote.
What the staining is telling you
Before the lab results come back, the marks around the house are a decent guide.
| What you see | Usually means | Typical fix |
|---|---|---|
| Brown or orange staining in the toilet cistern, on the washing, on paths | Iron | Oxidising iron removal system |
| Black staining, black specks in the kettle | Manganese | Iron removal system, ozone type if levels are high. Manganese is harder to shift than iron |
| White chalky deposits on elements, kettles and shower heads, soap will not lather | Hardness (calcium and magnesium) | Water softener, or ScaleProtect where a softener will not fit |
| White smears on glass that will not polish off, on mirrors and shower doors | Silica | Reverse osmosis. This is why we ask you to tick the silica test |
| Blue or green staining on baths and basins, green tinge in blonde hair | Acidic water dissolving your copper pipe | Neutraliser to raise the pH. Fix the cause, not the copper |
| Pinhole leaks appearing in copper pipework | Acidic water, same cause | Neutraliser. Worth acting on before you repipe |
| Rotten egg smell | Hydrogen sulphide, often with iron bacteria | Oxidising system, and usually a bore clean first |
| Cloudy or gritty water | Sediment and turbidity | Sediment filtration, backwashing if it is heavy |
The numbers that matter on the report
Units on a Hill Labs report are g/m³, which is the same as mg/L and the same as ppm.
| Parameter | Guideline | Why it matters |
|---|---|---|
| E. coli | Must be <1 per 100 mL | Any detection means faecal contamination. Do not drink it untreated |
| pH | 7.0 to 8.5 | Below 7 is corrosive. Rainwater sits around 5.7 naturally |
| Iron | 0.3 or less | Above this you get staining |
| Manganese | 0.04 staining, 0.10 taste | Stains at a tenth the level iron does |
| Hardness | 200 or less as CaCO₃ | Above this, scale becomes a real cost |
| Nitrate-N | 11.3 maximum | A health limit, not an aesthetic one. Infants under six months are the concern |
| Silica | No threshold, presence is what matters | Not a health issue, purely the glassware. If it shows up at all and glass is your complaint, reverse osmosis is the fix |
| Turbidity | 5 NTU or less | Cloudy water shields bacteria from UV |
Why one clear E. coli result is not the end of it
Read this before you rely on one result
This is the part we would rather you heard from us than found out the hard way.
An E. coli test is a snapshot of one bottle of water on one day. It is genuinely useful and worth doing. But on rainwater and bore supplies the result can change within hours, and the things that change it are ordinary: heavy rain washing roof debris into the tank, a dead bird or possum in the tank, surface water finding its way into a shallow bore, a flood, a dry spell followed by a downpour.
A clear result in January tells you very little about April. Most households on roof water build up a tolerance to what is normally in their own supply, which is why visitors and grandchildren are the ones who get sick.
The only way to be genuinely protected is continuous treatment.
That means either a well maintained UV system, with the lamp changed every 12 months and the sleeve kept clean, or TankSafe dosed to the tank on a schedule and checked with test strips.
Test the water to find out what you are dealing with. Treat the water to stay safe.
Send us the report
Email your Hill Labs certificate through, tell us your water source, roughly how many people are in the house, and what you are seeing around the place. We will come back with what you actually need.
On anything expensive it is worth getting right first time, and a certificate beats a guess every day of the week.
Prefer to talk it through? We install and service this gear around Waihi, Thames and the Coromandel every week. A real person picks up.
