Well Shock Kits Compared: Bleach, Pellets, Pro Service, and Ours

Four ways to shock a well, from a $5 jug to a $3,000 service call. Here is what each one is, what it costs, and which wells it fits, with the chemistry facts attributed to their sources.

Plain bleach from the store

about $5 to $15

Unscented 5.25% sodium hypochlorite, the extension-guide standby. Cheapest by far, and the weakest per gallon: you do all the volume math yourself, the dose is jug-and-guess, and there is no residual test unless you buy one separately. Everything in the bleach column of our chemistry comparison applies.

Chlorine sanitizer packs, like Well Safe

about $45

Pre-measured calcium hypochlorite, which is 65 to 75% available chlorine in pellet or powder form. Easier than jug math and made for potable wells, and still chlorine chemistry: one standard dose for a typical well rather than yours, the same pH and biofilm limits as bleach, and the killing power runs out fast in an iron-heavy well.

A pro shock treatment

about $80 to $650

A contractor doses the well for you, usually with the same chlorine chemistry, and a full well cleaning with brushing or redevelopment runs $1,500 to $3,000. You pay for the truck, the labor, and the license. For a failed casing or a stuck pump that is exactly the right buy.

This kit

from $399, about $497 for a typical well

Chlorine dioxide sachets counted to your well's own gallons, pulled from your state's official well record, at the manufacturer's published 20 ppm shock dose. Per the maker's lab data, the dose in the box carries the killing power of about 27 chlorine kits, and it comes with the residual test that proves the treatment held, PPE, and printed steps with your numbers written in.

Street prices are approximate figures from public listings and change. The chemistry behind the chlorine limits and the chlorine dioxide claims is laid out, with attribution, in chlorine dioxide vs bleach, and every dosing number we use is on the sources page. Well Safe is its maker's trademark; we mention it only to compare products.

The only kit on this page sized to your exact well.

Answer a few questions and we pull your well's dimensions from your state's official well record, then pack a chlorine dioxide kit to those exact numbers from $399. A contractor charges $1,500 to $3,000 for the same cleaning.

Find my well See what's in the kit

Straight answers

Are the $45 well sanitizer kits any good?

They are honest products for what they are: pre-measured chlorine for a typical well. If your water is near neutral pH, low in iron, and the problem is a one-time contamination, one can do the job. The wells they disappoint are alkaline, iron-heavy, or slimed with biofilm, which describes most wells that keep re-fouling.

Why is your kit ten times the price of a chlorine kit?

Because it is a different product, not a bigger bag of the same chemical. The box carries chlorine dioxide with the killing power of about 27 chlorine kits per the manufacturer's lab data, it is sized to your well's official record instead of a typical well, and it includes the residual test that turns the treatment from a guess into a result. Against the $1,500 to $3,000 contractor visit it replaces, it is the cheap option.

When should I hire a pro instead of using any kit?

When the well keeps testing positive after a proper shock and retest, when the casing or cap is damaged, when the pump needs pulling, or when you are not comfortable working at the wellhead. Disinfectant cannot fix a mechanical problem, and a licensed contractor can.

Do any of these kits work on iron bacteria?

Chlorine products mostly burn the surface of the biofilm that iron bacteria build, and the colony grows back. The manufacturer of our chlorine dioxide publishes data showing it penetrates and strips biofilm, which is why iron bacteria is the problem this kit was built around.

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