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    MWF 20" x 4.5" Twin Big Blue Whole House Rain Water Tank Filter System Complete with Ultraviolet Light & Positive Charged Water Magnet

    • Kills Bugs in fresh water
    • UV light - Ensure your safety
    • Whole house RAIN water treatment

    To view the current cartridge replacement price and information for this water filter please click here:

    Special Price: $1,197.99 $1,197.99 Regular Price: $1,299.99
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    Special Price: $1,197.99 $1,197.99 Regular Price: $1,299.99

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    Special Price: $1,197.99 $1,197.99 Regular Price: $1,299.99


    MWF 20" x 4.5" Twin Big Blue Whole House Rain Water Tank Filter System Complete with Ultraviolet Light & Positive Charged Water Magnet

    Whole House RAIN Water Tank filtration Systems.

    A user friendly unit designed to overcome the challenges and health RISKS associated with RAIN water today.

    This is a complete whole of house RAIN water tank filtration system designed to suit any sized home. Created to ensure useing & drinking the water in your home is safe to do so. Filters the debris from the water, removes any taste or odour, then the UV light sterilises the water and kills any bacteria or bugs present in the water at an incredible rate of up to 46 litres per minute, then the Magnet helps to soften the water prior to flowing into your home. Minimal unnoticeable pressure drop or flow rate drop with this high volume system designed to be installed after your pressure pump.

    If You are Wondering if you really need to treat Your Rain Water

    – PLEASE take a look at this link below…


    The BIG problem with our RAIN water supplies today

    The issue with our RAIN water supplies today is we are a drying country, less rainfall equals lower quality water. The longer the water sits in your tank without been flushed with new fresh rain water the more suceptabe it is to been contaminated. I dont want to put you off rain water but in my 20 plus years in the rain water tank industry you dont want to know the amount of dead animals i have removed from family home drinking water tanks.

    At this point I am thinking you will be wondering well how bad can it really be? Maybe i will just get a little stomack ache or sit on the toilet for a while at the worst case. But nothing could be further from the truth. When water is untreated, anything can grow in it.

    • Rain water is untreated water, water that is untreated with uv light or chemicals is a pleasant place for bacteria and bugs to grow.

    • Rain water is normally a low pH,  the lower the pH the more acidic the water. It is the acidic water that creates the problems.

    • Rain water attacks our homes, rain water can eat out all the copper pipes throughout your home, sometimes creating irreversible damage and costing tens of thousands of dollars to replace. If your concerned the first sign can be inside your kettle is all Black or you have blue / green staining on your white bathroom basin. Have your pH tested at the source.

    • Rain water consumed regularly can be a health hazard, it is no secret now days that acidic water is not prefered by our heath proffessionals. You only have to go online to see the massive amount of information against acidic water and drinks in general. Linking acid to arthritus, gout, cancer you name it the list is growing constantly. As humans we are healthier drinking alkaline water, you may want to consider this.

    • Rain water gets contaminated, Birds and other animals pollute the water catchment areas your rain water travels as it fills the tank. Very hard or impossible to stop the water been contaminated in this way.

    • Rain gets polluted on the way down,  As the clouds urupt and the rain falls down the water can pass through contaminated layers in the atmosphere. With so much air polution these days it is easy to understsand why.

    What can you do?

    You could firstly realise that RAIN water is not always ok to drink untreated. There can be all sorts of contamination in rain water. It is not a case of she’ll be right any more, we must take our water quality seriously.

    Understand if you continue to live without proper water filtration & sterilisation in your home, you may be risking your health and your family’s health consuming or washing in untreated water.

    You could install a user friendly whole house water filtration system to protect you, your family and your home. Read every word here and we will help you as we guide you through the simple process so you and your family can benefit living with the luxury of filtered treated sterilised conditioned water flowing throughout your home.

    A complete easy to use system

    A simple hands off system for those people who are not only serious about removing the sediment, taste & odour from their water supply but want to ensure the water is bug free and safe to consume.  

    This system is suitable for households who want the best water possible from their water source. This whole house Rain water filter system is a complete system ready to set up for any sized home. It is recommended for any size family. It treats water up to 46 litres per minute.

    Clean sterilised Bug free filtered water throughout your whole home is just a beautiful way to live.

    “ 7 Massive changes the “MWF Whole House 20" x 4.5" Twin Big Blue High Flow RAIN Water Filter System Complete with Ultra Violet Light & Positive Charged Water Magnet will create in your life”


    1.    Safe sterilised sediment free, taste & odour free water 


    2.    Sediment free hair which is easier to manage


    3.    Fresh smelling water throughout your whole home and in your shower 


    4.    Shower heads won't block up so you will get a great flow of soft water all over you in your shower


    5.    No more blocking sprinklers and reticulation systems


    6.    Home appliances will operate better, require fewer repairs and will last much longer


    7.  Protection from herbicides & pesticides



    How does the system do all that?

    As the water flows into the first stage of the Big Blue water filter this is where the water is screened and any sediment is removed ready for stage 2 where the high volume carbon block cartridge removes any taste, smell or odour. This carbon block cartridge is also responsible to protect from pesticides and herbicides.

    Then the disinfection takes place as clean filtered water flows through the chamber of the UV lamp.

    Once the water is cleansed & disinfected by the system it flows through the current of the water Magnet giving the water a Positive Charge and softening effect prior to flowing through your home.

    This whole house water filter is a strong robust filter that is specifically designed for places where high flow rate is required whether for your home, commercial or industrial use. Treating water up to 46 litres per minute.

    Step 1.

    The Filtration

    This whole house system is made up of 2 - 20” x 4.5” robust filter housings

    • The filter housing is supplied with a very strong support bracket

    • It has a air bleeder valve fitted to each filter housing cap

    • It comes with a 1” BSP inlet & outlet which can be reduced down in size very easily with a reducer

    • 5 year warranty on all housings

    Stage 1:

    5 Micron Pleated Washable Sediment Cartridge

    This cartridge is capable of removing Algae, Dirt, Particles, Rust, Sand, Sediment and Silt so your water is debris free and prepared for the next stage of this filtration process. Apart from removing the sediment from your water supply so you have cleaner water this filter is also the protection cartridge for the carbon block cartridge that follows, keeping it as clean as possible so it can work to it’s full potential removing contaminants.They are a high quality pleated sediment cartridge.

    These cartridges have a large holding capacity for a longer lifespan. Extremely important when the water contains sediment. These filters are our prefered sediment cartridge as they can be lightly rinsed and washed clean as required if you have heavy sediment.

    Stage 2 :

    5 Micron Silver Impregnated Carbon Block Cartridges 

    This carbon block cartridge will provide maximum removal of taste, smell or odour from your water supply. This is a great cartridges for removing organic’s, chemicals and microorganisms. Impregnated with silver to stop any bacteria growth inside the cartridge. All our Filter cartridges are manufactured from the highest quality, FDA-compliant raw materials with cutting-edge methods resulting in premium performance, reliability, absorption and flow rates. It is the volume of water and the contaminants in the water supply that will eventually dictate the lifespan of your cartridges but normaly these cartridges are changed annually..

    Ultra Violet Light Sterilisation:

    U/V System - 46 Ltr/min

    Commercial Grade - 316 Stainless Steel

    The ultra violet light has become a very popular way of steralising water without the use of chemicals in our modern world. The germicidal short wave radiation produced by the ultraviolet lamp kills any kind of microbiological contamination present in the water including bacteria and viruses.

    No micro-organism is known to be immune to UV.

    Features Include

    • Suitable for ALL OF HOUSE use or commercial or industrial.

    • Heavy duty UV lamps and quartz thimble

    • Commercial Grade Stainless Steel: 316 construction

    • Visual and audible Lamp Fail Alarms fitted to alert you

    • BSP threaded connections on same side for easy connections

    • Brackets are easy to install

    • Efficient, low pressure, high intensity UV lamps,

    • Lamps parallel to water flow

    • Using highest grade “hard glass” pure fused quartz to allow highest output.


    Flow: 46 lpm

    Systems Dimmensions: Length without plug 900mm

    Thimble: Quarts Dome type Thimble

    Port: 3/4” Male BSP

    Lamp Power: 40 watt

    Warranty: 12 months

    These are recommended levels, for use as a guideline for pre-treatment requirements:

    Hardness: <120ppm

    Turbidity: <1.0NTU

    Iron: <0.3ppm

    Manganese: <0.05ppm

    Tannins: <0.1ppm

    If your water quality parameters do not meet these criteria, please contact the distributor for pre-treatment recommendations.


    Pre-treatment must include at least a 5 micron sediment filter installed prior to the unit in order to ensure that particles capable of shielding pathogens are removed from the water prior to entering the system.

    The vessel is rated to 100 psi. The unit must be installed with an Australian Standards Approved Pressure Limiting Valve.

    A shut off valve must be installed both sides of the unit in order to turn the water off for servicing and to ensure the flow is restricted to the parameters of the unit.

    Ensure adequate clearance at the lamp connection end of the unit in order to safely remove the lamp from the chamber for servicing and lamp replacement.

    Space required is at least the length of the UV chamber.


    Before operating this unit, it must be earthed. Simply attach the supplied earthing cable onto the chamber. 

    Technical Data

    UV systems are not designed to be turned on and off as the water is required. UV lights are designed to be turned on and stay on. UV lamps take time to warm up and go through the stages before they are at full capacity to kill any bugs in the water. Always turn on the UV 15 minutes before you require to use it. UV lights can be turned off when going away for holidays or extended periods. Lamps should be changed once every year. The lamp may still be working, but after 1 year, the power will not be guaranteed to be strong enough to kill bacteria. The unit should be cleaned regularly. Hardness and other particles can build up on the quartz sleeve and on the inside of the UV chamber.

    Life: 9000 hours (1 year) lamp life Working Pressure 100PSI

    Last Stage, Magnetically Positive Charge the Water

    Here at the last stage is where the water passes through the positive charged magnet helping to break any surface tension and further soften the water. So even if you have a single tap on just trickling out the spout, your water will still be been treated. No water escapes the Magnetic current regardless of the flow rate.

    Magnetic Water Conditioner

    • All aluminium & stainless steel casing

    • Magnetic parts made of 100% top grade neodymium (Nd) magnet

    • 300% more Powerful than normal magnetic water conditioners

    • Ultra Strong Magnetic Power

    • Fits onto 12mm up to 18mm pipe

    • Dimensions 55mm x 45mm x 36mm

    • Easy to install with allen key provided


    Supplied with 2 quality gauges so you can tell how the system is performing at all times. Once the system is installed and working away you will be able to see your normal water pressure across the 2 gauges. These gauges allow you to know when to change the cartridges, so you don't waste money replacing cartridges that still have life left in them. A great asset to easily see how the cartridges are performing at all times.

    Cartridge Replacement Tool

    This handy moulded cartridge housing tool is used to break the seal or tighten up the cartridge housings when required. Normally only ever used when you do your annual cartridge replacement.



    Where to install your new water filter system

    This is a pressure system. This system is designed to be connected onto the pump delivery side of the pump. Which means install the system after the pump so the water is being pushed through the system. Please do not install this system on the suction side of any pump as they are not designed for suction. 


    The Big Blue High Flow Twin 20” x 4.5” housing is covered by a full 5 year warranty, the parts have a full 1 year warranty to ensure you have clean and safe hassle free drinking water.

    The UV lamp has a 12 month warranty.

    How To Sterilise & Prepare Your Water System

    Maintenance and Replacement Cartridges

    Cartridges are very easy to replace and need to be changed over every 12 months depending on your water quality and usage. The uv light should be replaced annually. The magnet is fitted into place once and will work forever. Take a look at the plumber as he changes the cartridges in the whole house water filter system in the video below.

    Automatic Cartridge Replacement Service

    When you invest in a water filtration product from My Water Filter, we like to ensure you have the best experience possible. We like to lend a hand & take care of you as best we can.

        • We happily monitor the cartridge life for you

        • When the cartridge is due for renewal, we then contact you

        • Once confirmed, we arrange everything and have a new replacement cartridge delivered to your door.

    Save Money

    Using this whole house water filter system stops sediment buildup throughout your home appliances ensureing they work to there full potential and last as long as possible. No more buying bottled water. Enjoy your own filtered steralised rain water fresh from the sky.


    When installing any water filtration device make sure the electricity and the main water supply is turned off prior to starting. Ensure you know what you are doing or have a qualified person to help install the filter. Take a look at the little how to install video in the Installation TAB.

    * Ensure you have a surge protection device to plug the light into - MUST HAVE - Even a $20 one will do

    * Stainless Steel Housing can withstand been in the weather but the electrical box is required to be kept dry out of the weather

    * The UV Globe is designed to - STAY ON AT ALL TIMES - But if you are going away you can turn this device off.

    The My Water Filter Difference

    “We love our products and what we do so below are just some of the things we do to make a difference” 

    We Give Together

    When you buy a water filter or home water solution from My Water Filter, at no extra cost to you, we give life changing drinking water to people in need on your behalf.

    Bit by bit we make a difference together. Check out our Giving page here.

    “We also deliver our products for FREE and you get a 30-day money back guarantee.
    The product comes with free insurance too!

    To Summarize

    If you have any questions or you'd like a friendly chat to discuss your requirements call:

    Rod on 1800 769 300.

    He is always Happy to have a chat and guide you along the correct path for your individual situation.


    Free Delivery Australia Wide
    Our 10 Guarantees
    30 Day Money Back Guarantee
    5 & 1 Year Warranty

    Product ID 507
    Manufacturer My Water Filter
    Model MWF 20" x 4.5" Twin Big Blue Whole House Rain Water Tank Filter System Complete with Ultraviolet Light & Positive Charged Water Magnet
    Dimensions Length without plug 900mm
    Warranty (Months) 12 Months
    For Water Type Rain Tank Water
    Filter Cartridges Stage 1 - 5 Micron Pleated Washable Sediment Cartridge <br/>
    Stage 2 - 5 Micron Silver Impregnated Carbon Block Cartridge <br/>
    Number of Filtration Stages Twin Stage
    Water Filter Cartridge Size 4.5" x 20" Big Blue
    Cartridge Replacement Period 12 Months
    Flow Rate 46 LPM


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    Customer Testimonials
    It really is a great feeling dealing with My Water Filter. It is rare nowadays to find a company that really cares about customer satisfaction after a sale has been made. I received my filter within two days of placing the order and I am really satisfied with it’s operation and ease of installation. Thank you kindly.
    You are welcome to share my feedback.
    Kind regards,

    Just a small note to thank you all for the great product and awesome service. The follow up call to my query within a few minutes and the ability to solve my problem (connection). Rod (expert) needs to get a job at my Bank LOL... Will be coming back once for a filter change soon. Thanks again.


    Really excellent customer service and great value for money. I’d recommend them to everyone

    Hi Rod

    The water tastes like nectar. So clear and sweet especially after putting it on the board. Had a lovely bath this morning... Which I don't normally do. Because I couldn't stand the smell that came off the steam before the filter went on. Is just awesome!!!! Is one of the best decision we ever made and well worth the effort..... Thank you for all your help .. and have a great day..


    "Rod, just to let you know that the Sprite High Output shower filter arrived today and it screwed easily and fits perfectly. We didn't need a spanner to put it on although we do have a hand held shower fitting so that could have been why. I had a shower and washed my hair and it was noticeably softer. In fact, I've been feeling it all day because it is so soft. I look forward to showering if my hair is going to be that soft all the time. I can honestly say that my hair hasn't been that soft since I washed it in rain water." Debra NSW

    Thank you Rod for your instant help and advice when I  found the lever firmly stuck  as I was setting up. You talked me round it, and all was well.  The water filter has been on the go from the time I connected it up,  much to my satisfaction.  I must say the 'My Water Filter" service and attention to detail is first class.  No one should  have any doubt about dealing with you, or the quality of your products, based on my experience.
    Best of luck

    Dear My Water Filter,

    This is my second year using the water filter from your company. I am very happy I found you when I did.

    I was using Stefani and then Brita before but they couldn’t last very long and gave me all sorts of problems. When I searched the internet for a recommended water filter, My Water Filter has such good reviews that I had to try it. The website is very user-friendly. The prices are very competitive. Most of all the quality is excellent! I never had to go back to your company for faulty replacements or complains or queries.

    The delivery only took a few days. The offers and promotions are better than all other water purification companies. 

    I must congratulate Rob and all My Water Filter team for the excellent job of providing the best to us!

    Yours sincerely,


    Thanks so much the filter arrived within a few days, easy to set up and use, I’ve had 2 water filters in the past that chill the water the motors always go around 12 months old, this has a good pourer that fills your bottle quickly. Much better I just store the water in the fridge once filtered. Very Happy.

    Thank you for all the help you provided over the phone. I'm pleased to say my water filter arrived safely and is now up and running. At last we have beautiful fluoride free water to drink.

    I think it's great you give back to others and my experience in purchasing with you has been hassle free and pleasant.

    "Rod was an excellent find and I’ll definitely be using him again in the future."
    Anton Klemm