Knowing how to choose a water tank helps you avoid two common problems: running out of water in the shower because the tank is too small, or paying for one you never fill. In Mexico, a tinaco is the water tank that sits on the roof and feeds the house by gravity. Searches for “tinaco” grew 18% in the last 12 months, according to Google Trends, so you are not alone. This guide is educational, with no brands or prices, so you can decide with confidence.
How to choose a water tank: size for your household
Size depends on how many people live in the home. As a reference, a plastic-tank manufacturer’s data sheet gives this relationship for vertical tanks:
| Capacity | People supplied (reference) |
|---|---|
| 450 liters | 2 |
| 600 liters | 3 |
| 750 liters | 4 |
| 1,100 liters | 5 |
| 2,500 liters | 10 |
This table comes from a single manufacturer and is a general guide. If your household does laundry often, has a garden, pets or frequent guests, go up a size [VERIFICAR: daily water use per person in your area]. If water reaches your neighborhood on a rotating schedule or at low pressure, more capacity or a cistern can give you peace of mind. Consider space too: a vertical 1,100-liter tank is 1.10 m in diameter and 1.40 m tall, according to the same sheet.
Vertical or horizontal tank
Both come in similar capacities. The manufacturer’s sheet shows a horizontal 1,100-liter tank that is 1.30 m long and 1.21 m high. The practical difference is space: one takes more height, the other more floor area. Measure your roof or the spot where it will go, and confirm the floor can bear the weight of a full tank [VERIFICAR: weight your slab can support; consult an engineer or architect].
Materials: what is on the market
Plastic tanks made of polyethylene are the most common in the data sheets we reviewed. Two details to look for:
- Layers. Some are three-layer tanks: one manufacturer’s sheet describes a beige outer layer, a white inner layer and a coating with an antibacterial layer. A light inner layer makes it easier to see dirt when you clean, and the outer layer aims to protect against light.
- Potable water only. Check that the tank is designed to store water for human use.
Other materials exist, such as fiberglass or stainless steel. A news article estimates a service life of 10 to 15 years for polyethylene, 15 to 20 years for fiberglass and more than 20 to 30 years for stainless steel with good maintenance [VERIFICAR: real service life by material and conditions; no technical source]. Signs it is time to replace a tank: cracks, scratches, malfunctions, or material shedding particles into the water.
The standard to look for
The Mexican standard NMX-C-374-ONNCCE-CNCP-2012 sets the specifications and test methods for prefabricated tanks and cisterns. It has been in force since November 18, 2012, according to the Ministry of Economy’s standards catalog. Ask the seller whether the tank complies, and request the data sheet in writing.
Installation: what makes the difference
- Flat surface. Place the tank on a flat base that supports its full diameter.
- Height for pressure. One data sheet recommends placing the tank about 2 meters above the highest shower, measured from the tank outlet, for good pressure.
- Valve and float. The float closes the inlet when the tank is full to prevent overflow. Check that they work properly.
- Lid closed. This keeps out dirt, mosquitoes and rodents.
Maintenance: how often to clean a tinaco
The municipal water and sanitation board of Chihuahua (JMAS) recommends cleaning the tank every 6 months, or sooner if you notice dirt or odor in the water. An Excélsior article reports that the federal Ministry of Health recommends doing it at least twice a year. Some manufacturers suggest other frequencies, even every 3 months, so check your tank’s manual.
Basic steps, according to those sources:
- Disconnect the pump (if you have one) and close the inlet valve.
- Empty the tank, leaving about 10 to 15 cm of water for scrubbing.
- Remove the float and scrub walls and floor with a clean broom or brush.
- Rinse with clean water and wipe dry with a clean cloth.
- Disinfect with a chlorine and water solution, spraying the walls and letting it sit 20 to 30 minutes [VERIFICAR: exact chlorine dose; follow the product label].
- Rinse, put the float back, close the lid tightly and refill.
Do not use detergent, soap or corrosive products, because they can contaminate the water. A good rule: if you can no longer clearly see the bottom of the tank, it is time to clean it. Write down the date of each cleaning so you do not forget.
Frequently asked questions
What tank do I need for a family of 4?
As one manufacturer’s reference, a 750-liter tank supplies 4 people. If your use is high or water arrives infrequently, consider 1,100 liters.
How often should I wash the tank?
At least every 6 months, or sooner if you see dirt or notice an odor.
Is a three-layer tank better?
The layers aim to protect the water and make inspection easier, but what matters is that it meets the standard and is made for potable water.
Where should it be installed?
On a flat surface and about 2 meters above the highest shower, according to a data sheet.
Related reading
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If you want to know what to check in the tank and the plumbing of a house before you decide, message us on WhatsApp at 55 8418 4789 and we will guide you.