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Larger High Capacity Extra / Spare Reverse Osmosis Tank 18L

Larger High Capacity Extra / Spare Reverse Osmosis Tank 18L

More about your Larger High Capacity Extra / Spare Reverse Osmosis Tank 18L

A High Quality, Fully-Tested Product

Brand New. Straight From The Factory

Full Fitting Instructions Provided

Easy Installation - Friendly Support

July Summer Sale
£110.00INC VAT
Only 182 in stock at this price | Available for next day delivery
guaranteed-fit
UK Water Filters Promise

If you change your mind about your purchase, you can return it for free, within 90 days, for a full refund.

Free Delivery & Returns
Order before 3pm for same day dispatch today
"Absolutely outstanding service. These folks really do know how to do an amazing job. I honestly am so delighted with everything they have done. The kit is superb, water tastes wonderful. They always send the filters quickly and have answered many questions I had when fitting the system and the replacement filters. I highly recommend them. Such lovely staff, always so helpful and easy to contact when you need advice. So very glad I went with them and so grateful to them for such a high quality service. 🤩 great work 🤩"
Kelly - June 2025

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Product Description

Reverse Osmosis 18 Litre Tank

This high quality RO Water Tank is a great replacement for standard size tanks.

Standard domestic / light-use RO systems come with either a 9 litre or 12 litre tank. That's fine for most situations. But the problem is that if you drain the tank in one go, you have to wait for it to fill up again. This can take an hour plus - depending on your water pressure.

This higher volume tank let's you take much more purified water in one go.

Note that this tank can connect up with other tanks for even higher capacity. You simply need a T-Piece to join them together then run them towards the outlet faucet. Ask us for further information on this.


My order arrived promptly and it is also fitted. Thanks for your follow up check it demonstrates an excellent attitude towards Customer Service. Mr A Wood


Features summary:

  • Supplied complete with Tank Valve with 1/4" Push Fitting
  • Ready for immediate installation
  • verything you need to install the system is supplied
  • Simple installation no plumber needed
  • Reliable operation
  • Free Technical Helpline to assist with any problem
  • No Quibble ONE YEAR Money Back Guarantee
  • Buy with complete confidenc
  • Three year full parts warranty
  • strong>Easy to use

ORDER ANYTIME Day or Night 24/7 for NEXT DAY DELIVERY

With FREE Delivery

Immediate Dispatch

Purchase with Total Confidence

Money Back Guarantee

Click here for delivery information

No hidden extras

If you don't like what you get, send it back for a full no quibble refund.

If for any reason you decide to return your purchase we promise you a no questions asked THREE MONTH Money Back Guarantee. Click here to read the "large print" about our Money Back Guarantee.

PLUS We'll even pay your return postage !

Please order now to secure today's sale price.

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Product Code: RO-TANK-18L

High Capacity Reverse Osmosis Tank
Technical Information

Dimensions

Height: 38 cm

Diameter: 28 cm

Weight (empty): 7 kg Weight (full): 57 kg

(Note: The storage vessel can be placed several yards from the RO unit. Simply ask us for extra tubing).


How Much Water Does it Store?

When considering how much water is produced by any Reverse Osmosis filter, the most important factor is the size of your RO tank.

This is because your RO filter system feeds the tank then stops when it's full.

Here's how it works: When you draw water from your RO you are taking water from the tank. As the tank empties the system refills it at the "production rate" (eg typically 50 GPD) up to the tank's capacity.

Now, in addition to this, you have to consider that the tank's size is based on the actual physical dimension and not the amount of water it contains.

You have to also take into account the internal bladder that holds the water inside of the tank.

For example, the bladder inside this unit's nominal 18 litre tank will actually hold about 12 to 15 litres of water. If you draw all the water out of the tank it will take anywhere from half an hour to 3 hours to fill up again - depending on your incoming water pressure.

Therefore the amount of water this size produces is 12 to 15 litres per average of 2 hours - on a stop/start basis. (Note that you only have to wait for more water if you fully drain the tank in one go. In our experience this happens very rarely).


Product CODE 18L-RO-TANK



ORDER ANYTIME Day or Night 24/7 for NEXT DAY DELIVERY

With FREE Delivery

Immediate Dispatch

Purchase with Total Confidence

Money Back Guarantee

Click here for delivery information

No hidden extras

If you don't like what you get, send it back for a full no quibble refund.

If for any reason you decide to return your purchase we promise you a no questions asked THREE MONTH Money Back Guarantee. Click here to read the "large print" about our Money Back Guarantee.

PLUS We'll even pay your return postage !

Please order now to secure today's sale price.

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SKU: RO-TANK-18L
Delivery & Returns

Free Second Class - up to 5 days (90% arrive in 3 days)

First Class - up to 2 days (95% next day delivery)

Free Returns and Money Back Guarantee. Full details

Free Lifetime Support

If you have any problems

... or concerns with your purchase we are here to help.

We are not "here today gone tomorrow" merchants.

A quick look at our Customer Feedback

... and our Money Back Guarantee should help reassure you that we are an honest firm who will give you a first class, long term service.

How to get help

Call our help line on 020 8761 6611 at any time during UK office hours ie 9 am to 6 pm

Or email us for a rapid response.

Our policy is always to get back to you within an hour - or one working day at most.

Returns

In addition to your 3 Year Warranty, if for any reason you change your mind about your purchase within 90 days of receiving the goods, you can return your product for a full and complete refund *

PLUS we will pay for your return postage (UK only)

*This applies to individuals/ consumers using the products in domestic settings. Businesses please see our terms and conditions

Delivery Times

Order before 3 pm on any working day and we guarantee your order will be sent out the same day (not on weekends)

(To be honest we often manage to send them even after 3pm. But we can't promise that).

All prices on the website include delivery charges and VAT except where stated otherwise.

Delivery Charges

Your Standard "Free Delivery Included" is Second Class

This usually takes between 3 to 5 working days ie does not count weekends or Bank Holidays

Pay Extra for First Class

You also have the option at checkout to pay extra for First Class.

This should result in next day working delivery to mainland UK.

BUT please note while 95% do arrive next day this is not guaranteed.

However arrival within two working days is almost certain.

You can see your delivery costs at the checkout stage before you buy.

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Over 8,000 reasons to buy from us

Well Established

We are a family run business who value our customers. We've been trading for over twenty five years. So we won't be "here today gone tomorrow". Your Money Back Guarantees and Warranties will be safe.

Fully Accredited

Members of Safebuy the leading Consumer Assurance Scheme for online retailers approved under the Trading Standards Institute's Consumer Codes Approval Scheme.

Repeat Customers

Many of our clients have been buying filters from us for several years. Over 95% keep coming back to renew their filter because we offer a friendly, helpful service and great value prices. Checkout our TrustPilot reviews.

We’re Trustworthy

We have a huge number of great independent testimonials. For example on the Approved Consumer Code Directory for the Trading Standards Institute and on Google Certified Shops.