---
product_id: 66564551
title: "GTS3 3 Gallon RO Water Filtration Expansion Tank, Compact"
brand: "tankro"
price: "€ 253.58"
currency: EUR
in_stock: true
reviews_count: 13
category: "Tank Ro"
url: https://www.desertcart.hr/products/66564551-gts3-3-gallon-ro-water-filtration-expansion-tank-compact
store_origin: HR
region: Croatia
---

# 3-gallon capacity 1/4” quick connect valve durable steel construction GTS3 3 Gallon RO Water Filtration Expansion Tank, Compact

**Brand:** tankro
**Price:** € 253.58
**Availability:** ✅ In Stock

## Summary

> 💧 Elevate your hydration game with the ultimate RO expansion tank—because clean water waits for no one!

## Quick Answers

- **What is this?** GTS3 3 Gallon RO Water Filtration Expansion Tank, Compact by tankro
- **How much does it cost?** € 253.58 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.hr](https://www.desertcart.hr/products/66564551-gts3-3-gallon-ro-water-filtration-expansion-tank-compact)

## Best For

- tankro enthusiasts

## Why This Product

- Trusted tankro brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Built to Last:** Rigorously tested deep-drawn steel tank with precision welding, backed by a 1-year warranty for peace of mind.
- • **Compact Powerhouse:** Fits seamlessly under most sinks (14x9x9 inches) for sleek, space-saving water storage.
- • **On-Demand Refreshment:** Stores up to 2.2 gallons of filtered water, delivering consistent flow at up to 0.8 gallons per minute.
- • **Pure & Safe Hydration:** Crafted from 100% food-grade, BPA-free materials ensuring contaminant-free water every time.
- • **Effortless Installation:** Includes a 1/4” quick connect ball valve for a hassle-free, tool-free setup—upgrade your RO system in minutes.

## Overview

The GTS3 3 Gallon RO Water Filtration Expansion Tank is a compact, durable, and easy-to-install solution designed to enhance your reverse osmosis system. Made from 100% food-grade, BPA-free materials and constructed with precision-welded steel, it stores up to 2.2 gallons of purified water for on-demand use. Featuring a 1/4” quick connect ball valve and universal fit, it ensures seamless integration under most kitchen sinks, delivering reliable, contaminant-free water flow with a 1-year warranty for lasting value.

## Description

TankRO GTS3 3 Gallon RO Water Filtration Expansion Tank, Compact | White Finish, Includes 1/4" Ball Valve, Durable Steel Construction, Universal Fit for RO Units - desertcart.com

Review: Hi, quality product top-notch. - If are struggling with low pressure? Intermittent working and slow water from the osmosis system, this is the way to go. This reserve water tank was the answer to my problem. The installation was easy, a filtration system through that is absolutely no problem. Whatsoever value for your money is on top. You can't beat the price. It is cheaper than trying to have somebody come out. And go through the system, as for the quality of the tank, it is top-notch.
Review: Great upgrade for my RO system - I’ve had a RO system for many years and had a smaller tank on it. The bladder finally went and I decided to upgrade and it is performing very well. I followed the instructions to clear the tank after one minute of operation and then again after four hours of operation. There is no residual taste. When hooking it up to your system, I would make sure to just leave the pressure where it’s at as it is typical for most systems. If it doesn’t work for you then adjust it. Furthermore, when you put the Plastic valve on the top, I would use not only Teflon tape but also some dope as well. I had to return the first tank they sent as it was not wrapped well and came dented, but to be fair it did work for the short period of time before a replacement was sent, the company was quite responsive. As an FYI, the second tank came much better wrapped. It was undamaged. they had clearly realized they had a problem so they change the wrapping.

## Features

- Reverse Osmosis Tank: Made from 100% food grade materials, this RO water tank stores and keeps your water free from any impurities and harsh chemicals. The perfect addition to any RO water system.
- Easy to Install Water Tank: RO tank replacements include free tank ball valve for easy set-up and replacement with 1⁄4” quick connect design.
- Durable Water Storage Tank: This RO water tank is rigorously tested for quality and durability and includes a 1-year warranty.
- High Quality Water Tank: This water storage tank is made from durable deep-drawn steel domes with precision welding to ensure long lasting value for your RO water system.
- Water Tank Dimensions: This compact water tank is designed (14 x 9 x 9) to fit under most kitchen sinks. Stores up to 2.2 gallons of water for on-demand filtered drinking water.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B079YZ8THK |
| Best Sellers Rank | #61,332 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #113 in Under-Sink & Countertop Filtration |
| Brand | tankRo |
| Brand Name | tankRo |
| Capacity | 3 gallons |
| Container Type | Tank |
| Customer Reviews | 4.5 out of 5 stars 1,405 Reviews |
| Included Components | Tank |
| Installation Type | Under Sink |
| Item Dimensions L x W x H | 9"L x 9"W x 14"H |
| Item Highlight | White Finish, Includes 1/4" Ball Valve, Durable Steel Construction, Universal Fit for RO Units |
| Item Weight | 6 pounds |
| LowerTemperature Range | 33 °F |
| Manufacturer | tankRo |
| Material | BPA Free |
| Material Type | BPA Free |
| Maximum Flow Rate | 0.8 gpm |
| Model Name | GTS3 |
| Model Number | GTS3 |
| Number of Items | 1 |
| Operating Pressure Range | 5-100 psi |
| Other Special Features of the Product | Durable |
| Part Number | GTS3 |
| Power Source | Adapter |
| Product Dimensions | 9"L x 9"W x 14"H |
| Purification Method | Reverse Osmosis |
| Special Feature | Durable |
| Supported Water TDS Level Maximum (PPM) | 2000 |
| UPC | 653590999287 |
| Upper Temperature Rating | 100 °F |

## Product Details

- **Brand:** tankRo
- **Capacity:** 3 gallons
- **Included Components:** Tank
- **Installation Type:** Under Sink
- **Material:** BPA Free
- **Package Information:** Tank
- **Power Source:** Adapter
- **Product Dimensions:** 9"L x 9"W x 14"H
- **Purification Method:** Reverse Osmosis
- **Special Feature:** Durable

## Images

![GTS3 3 Gallon RO Water Filtration Expansion Tank, Compact - Image 1](https://m.media-amazon.com/images/I/61ttQ1+cTAL.jpg)

## Available Options

This product comes in different **Size** options.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Hi, quality product top-notch.
*by J***Z on July 1, 2026*

If are struggling with low pressure? Intermittent working and slow water from the osmosis system, this is the way to go. This reserve water tank was the answer to my problem. The installation was easy, a filtration system through that is absolutely no problem. Whatsoever value for your money is on top. You can't beat the price. It is cheaper than trying to have somebody come out. And go through the system, as for the quality of the tank, it is top-notch.

### ⭐⭐⭐⭐⭐ Great upgrade for my RO system
*by F***4 on December 21, 2024*

I’ve had a RO system for many years and had a smaller tank on it. The bladder finally went and I decided to upgrade and it is performing very well. I followed the instructions to clear the tank after one minute of operation and then again after four hours of operation. There is no residual taste. When hooking it up to your system, I would make sure to just leave the pressure where it’s at as it is typical for most systems. If it doesn’t work for you then adjust it. Furthermore, when you put the Plastic valve on the top, I would use not only Teflon tape but also some dope as well. I had to return the first tank they sent as it was not wrapped well and came dented, but to be fair it did work for the short period of time before a replacement was sent, the company was quite responsive. As an FYI, the second tank came much better wrapped. It was undamaged. they had clearly realized they had a problem so they change the wrapping.

### ⭐⭐⭐⭐⭐ Ditch that small tank for this - you will be glad you did. SO. MUCH. WATER!
*by B***Y on September 11, 2025*

Original RO system came with a paltry 3 gallon tank, of which only 1.8 gallons was for water storage. I didn't know how awful that was until the membrane in that tank died. Determined to ensure we always have enough RO and plenty of pressure in the line, I doubled the desired capacity, and then DOUBLED it AGAIN. So, the 8 desired gallons of liquid required a 10-12 gallon tank. The tank came with ZERO installation hardware. I stole the old valve from the old tank which worked out just fine. By morning, we had 8 gallons of RO water flowing. I strongly recommend this tank!

## Frequently Bought Together

- TankRO - RO Water Filtration System Expansion Tank - 3 Gallon Compact Reverse Osmosis Water Storage Pressure Tank With Free 1/4" Ball Valve
- Metpure Quick Connect Tank Ball Valve with Gasket For Water Purification Systems And Reverse Osmosis System Pressurized Water Storage Tank (1/4" Female NPT x 3/8" OD Quick Connect)
- John Guest 3/8 Inch O.D. Tube Size x 1/4 Inch NPTF Speedfit to Female Shut Off Valve, Push to Connect Plastic Plumbing Fitting, PPSV501222WP

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*Product available on Desertcart Croatia*
*Store origin: HR*
*Last updated: 2026-09-17*