Why we started this
Nobody told us our tank needed cleaning.
We were in disbelief when we saw the underground tank that supplies our sinks and showers. We are a foreign family who moved to Vallarta three years ago. Cleaning our tank was something we simply didn’t know we had to do. The sludge we found — in the same water we use to shower and brush our teeth — was no joke.
I started Tank Goodness because this is a problem I believe few, my family included, know they have.
What we do
Document. Not just clean.
- Drain the underground tank (cistern), remove sludge and sediment by hand.
- Pressure-wash walls, floor and ceiling, then disinfect and rinse.
- Only after the cistern is clean, wash the rooftop tinaco and flush the lines.
- Provide a written record of what we find and any issues noticed in the tank and tinaco.
- Send photo documentation of the inside of the tanks, including a set of before and after photos.
- Structural check while we are inside — cracks, seals, lids, anything that could let contamination back in.
- Professional confined-space procedure.
- We arrive when we say we will, with our own equipment.
We come out, open the tank and show you what is inside. We tell you what we find. You make the decision.
Available before and after the clean, or both — ask and we will quote it with the job. A water analysis is a measurement of the sample taken at the time and place. It is not a certification of ongoing water quality.
COFEPRIS, the federal health regulator, recommends a minimum of one cleaning every six months, so two visits a year is a good start.
Ask for a look at no costTell us about your tank
Two minutes. Then we quote you.
Fill in the form and it creates a WhatsApp message with the details we need to price the job.
What’s actually down there
Warm water, no chlorine, years of sediment
Municipal water arrives with chlorine in it. Chlorine fades while water sits — faster when the water is warm — Vallarta is warm all year. Once it’s gone, bacteria grows and creates a bio-sludge. Every tap in your house is fed with water exposed to this sludge. Few understand how serious this is. Your water source is a literal swamp.
0.2–1.5 mg/L free chlorine required at your tap under Mexican standards (NOM-127). 6 months between cleanings, per COFEPRIS. 50% of Guadalajara homes tested over the coliform limit at the tank outlet (Rubino et al., International Journal of Environmental Research and Public Health, 2019).
A real file
One house in a five-year-old coto
PLACEHOLDER FIGURES — do not publish until a real signed report exists.
Two thousand litres, never cleaned since it was built. Free chlorine at the tap 0.05 → 0.80 mg/L · Total coliforms 240 → 0 NMP/100 mL · Heterotrophic bacteria 1,850 → 35 CFU/mL · Pseudomonas aeruginosa detected → not detected · Sediment on the floor 6 → 0 cm
Your filtration system doesn’t fix this. A filter works on water that’s already reasonably clean. With sludge upstream, cartridges clog fast, and carbon filters strip the last of the chlorine that was holding bacteria back.