1 / 7iSpring T20M 20-Gallon Pre-Pressurized RO Storage Tank
The iSpring T20M is a pre-pressurized storage tank for reverse-osmosis systems, with a listing capacity of 20 gallons and title-claimed water storage capacity of 14 gallons. Its substantial listed dimensions make installation space and the capacity distinction important to check before buying.
At a glance
- Manufacturer feature copy says the tank can be positioned vertically or horizontally.
- The listing claims NSF certification and describes third-party testing to meet NSF and ANSI Standards.
- The tank is intended to store reverse-osmosis water, rather than perform filtration itself.
Reference price: $218.99
Price checked: Nov 14, 2026
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Pros and cons
Pros
- The manufacturer describes vertical or horizontal operation, which may give more options when planning the installation.
- Customer feedback reports easy installation and strong RO faucet pressure, though experiences are individual and not guaranteed.
Cons
- The listed dimensions and weight may make placement challenging in a typical under-sink cabinet.
Technical specifications
14 specifications| Brand | iSpring |
|---|---|
| Model | 20 Gallon Pre-Pressurized Water Storage Tank for Reverse Osmosis (RO) Systems |
| Model number | T20M |
| Listed capacity | 20 gallons |
|---|---|
| Installation type | Under Sink |
| Purification method | Storage RO Water |
| Maximum supported water TDS level | 500 |
| Dimensions listed | 16"L x 16"W x 30"H |
|---|---|
| Weight listed | 14.5 kg |
| Positioning | The tank works efficiently in either vertical or horizontal position |
| Material listed | Stainless Steel |
|---|---|
| Special feature | NSF certified |
| Lower temperature range | 40 °F |
| Upper temperature rating | 100.12 °F |
What to know before buying
Listing details to confirm
Listing details are inconsistent: the title claims 14 gallons of water storage while the specifications list a 20-gallon capacity. The listing also calls the unit under-sink but gives dimensions of 16"L x 16"W x 30"H. Confirm the capacity measurement and available installation space before purchase. Customer feedback also reports bladder durability concerns and mixed experiences with tubing-connection leaks, which are reported experiences rather than confirmed defects.
What’s in the box
- RO tankIncluded
- Shut-off valveCheck selected pack
- Tank connectorCheck selected pack
- Tank standCheck selected pack
Check which accessories are included in your selected pack before buying.
Who is it for?
A good fit for
- RO system owners seeking a pre-pressurized water storage tank and able to accommodate its listed dimensions.
- Buyers who can use either vertical or horizontal placement and want a tank rather than a complete RO filtration system.
Less suited to
- Buyers who need a compact tank for a restricted under-sink cabinet.
- Buyers who require a confirmed usable storage volume before ordering, since the listing gives both 14- and 20-gallon claims.
Customer reviews on Amazon
- 5 stars
82% 82% - 4 stars
10% 10% - 3 stars
4% 4% - 2 stars
1% 1% - 1 star
3% 3%
Customer feedback highlights perceived quality, ease of installation and water pressure at the RO faucet, while some customers report bladder durability concerns and experiences with tubing-connection leaks are mixed. Reports of more than four gallons when fully charged give some context for actual water availability, but do not resolve the listing's conflicting 14- and 20-gallon capacity figures. These are customer reports, not guaranteed outcomes.
Positive themes
- Customers describe the tank as good quality and easy to install.
- Some customers report strong water pressure from the RO faucet and useful water capacity.
Negative themes
- Some customers report bladder failure after a couple of years.
Mixed feedback
- Leakage experiences vary, including reports of trouble at tubing connections and reports of no leakage.
Frequently asked questions
Is the tank's storage capacity 14 or 20 gallons?
The title claims 14 gallons of water storage capacity, while the specifications list 20 gallons. These are conflicting listing details, so confirm the applicable capacity before buying.
Can the tank be installed horizontally?
The manufacturer says it works in either vertical or horizontal position. Allow for the listed dimensions and confirm that your installation and connections accommodate the chosen position.
Does this tank filter water?
The listing describes it as storing RO water. It is a storage tank, not a complete reverse-osmosis filtration system.
What comes with the tank?
The listing's included-components field names an RO tank. Feature copy also claims a shut-off valve, tank connector and tank stand are included, so check the selected listing's package details for those items.
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