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High Performance Filtration | Whole House Calcite Water Filter | Adjust pH from Acidic to Neutral | 52" X 12" (GT1-18C)

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Whole House Calcite Water Filter | Adjust pH from Acidic to Neutral | 52" x 12" (GT1-18C)

Suitable for tank water with a pH below 7 to help protect your plumbing fixtures/copper pipework from corrosion and degradation. Please contact us prior to ordering to ensure that you are getting the correct system for your requirements. 

Diagram example of how the GT1-18C Calcite Vessel should be installed alongside a Twin Whole House UV Rain Water Treatment System.
(Note: Tank, Pump, Twin Big Blue Filter Housings, UV System, Weatherproof UV Enclosure, Single Socket Surge Protector & Bypass Valves not included).

Kit Includes:

  • 1x Media Vessel
  • 1x Runxin 1" Multiport Backwash Valve & Lateral Drop Tube
  • 1x 20kg Bag Filter Sand/Gravel
  • 4x 20kg Bags Calcite Filter Media
  • Instruction/Warranty Sheet

Specifications & Technical Data:

  • Vessel Size: 52" x 12"
  • Polyethylene Inner Shell
  • Max Pressure: 150 PSI (10.5 Bar)
  • Max Temperature: 50 C (122 F)
  • Min Temperature: 1 C (34 F)
  • Max Vacuum: 140mmHg (5.5" Hg) Negative Pressure (Do NOT exceed Specifications)
  • Vessel approved for water filtration use only. All other applications must be approved by the manufacturer.
  • Do not use for pneumatic or Hydro-pneumatic application.
  • Vessel must NOT be exposed to temperatures lower than -30 Degrees Celcius.
  • This Vessel complies with all requirements of P.E.D 97/23/EC Directive.
  • This water pressure vessel is tested & compliant to NSF/ANSI Standard 44 for Material and Structual Requirements Only.

Required for Installation - Add to Cart or Supply Your Own:

GT15-1 1" Spring Loaded Check Valve (Prevents Backflow)

This media vessel will require a 1-way valve (check valve) installed behind it to avoid negative pressure in the system caused by a sudden backflow of water. It is also recommended that you include an isolation valve for easy maintenance when re-filling the vessel.

GT36-83N - Neoprene UV-Resistant FRP Tank Cover (Recommended)

Constructed with UV-resistant neoprene, this tank cover ensures optimal performance even in the most demanding environments. Whether you need protection against sunlight, extreme temperatures, or other exposure, this cover has got you covered. It effectively shields your tanks from harmful UV rays, preventing degradation and extending their lifespan.

Optional Add On - Media Funnel:

The specially-designed Media Funnel helps you fill the vessel without spilling expensive media, or getting the media stuck inside the drop tube! Use this funnel to save yourself from the hassle of having to try and push the drop tube back down into the dense media (because you've accidentally dropped media inside the tube, and had to pull the tube out to empty it)!

Why do you need a calcite filter for rainwater?

The issue of tank water acidity is of particular concern for customers with the poly/steel tank + copper pipes combo - this must be addressed in order to prevent copper pipe corrosion and pinhole leaks in your pipework later down the track (which is very costly to fix)! 

Rain water is commonly known to be in a very acidic state (around a pH of 5) naturally, and it is only when it comes into contact with earth or other organic material that the pH rises to neutral and even alkaline levels. However when you have clean gutters and a new clean poly tank (or a poly-lined steel tank), there is no organic or inorganic matter to dissolve into the water to raise the pH, thus you are left with highly acidic water sitting in your tank. This can cause extensive health issues in the long term, but it may also affect your plumbing work throughout your house. Copper is easily corroded by acidic water - if this is happening in your home, you will notice a blue/green tinge which is a signal that copper is dissolving into your water. Acidic water works its way from the inside out and if left long enough untreated, may cause your entire copper pipework to fail and need replacing.

Have you checked for signs of copper pipe corrosion in your home? Above are some examples of copper pipe corrosion, which is easily detected by the presence of blue-green staining around drains, fixtures and faucets. In the worst-case scenario, copper pipe corrosion will start with pinhole leaks, progress to multiple holes, and will eventually require you to replace the entirety of the copper pipework of your home!

This brings us to the solution to acidic water - the Calcite Filter. The GT1-18 Calcite Vessel filter features two stages of filtration:

  1. Stage 1: Filter Gravel - Gravel acts as a sand filter, filtering out dirt, sediment, and other particulates in the water.
  2. Stage 2: Calcite Marble - The way Calcite Marble filtration works, is by dissolving traces of calcium into the water to help buffer the pH back to neutral. The Calcite Marble supplied with this system is of the highest quality available in Australia, providing a consistent pH buffer and a long filtering life. On average you will need to refill about 1/2 to 1 bag full of Calcite Marble per year (which depends on water usage + pH of incoming water). We recommend that you buy a few spare bags of Calcite Marble with your order so you have it on hand for when you need to top up the calcite filter.

The drop tube is pre-cut to length and fits snugly in the centre hole of the vessel (there is a port at the bottom of the vessel that the drop tube will sit in snugly). There will be no need to cut the drop tube. The system is also fitted with a Manual Multi-Port Valve for easy and efficient backwashing of the system, again, saving you time and effort in maintaining the system.

Do I need Magnesium pH Booster Filter Media?

Please contact us prior to ordering pH Booster Filter Media. This will ensure that you are receiving the correct product for your intended purpose.

If you are considering a Calcite Vessel as part of your tank filtration set up AND the pH of your tank water is below pH. 5, you may need to add pH Booster Filter Media (Magnesium) to get the correct final pH. Adding pH Booster Filter Media to water with a pH below 5 alters the water chemistry to enable the uptake of Calcite (Calcium). For this intended use you will see the pH range anywhere from ph. 7-8 or higher depending on the pH of the incoming water. Note: when using magnesium as a pH booster, the pH will likely be above 8 when the media is new and will gradually lower over time. We recommend that you buy a spare bag of Magnesium pH Booster with your order so you have it on hand for when you need to top up the filter.

Please note that magnesium can leave a slight residual metallic taste in the water. This taste is easily removed by carbon post-filtration (included in this kit) which will produce clean, sweet-tasting water.

Using Magnesium & Calcite Together + Maintenance/Refill Instructions

Calcite and Magnesium are two common types of filter media used for pH adjustments in Rain or Bore Water. These types of media will slowly dissolve into the water over time which will mean that they require replenishment to maintain high flow rate capacity.

  • When first using a pH filter media, follow the same backwash and rinse cycles as mentioned in the system instruction manual.
  • In cases where Magnesium and Calcite are used together, add the calcite to the vessel first, then add the Magnesium on top. Ensure that you do not overfill the vessel.
    • If the pH is around 5, fill the vessel with a ratio of 80kg (4x 20kg boxes) of Calcite to 7.5kg (approx. 1/3 bag) of Magnesium.
    • If the pH is around 4.5, fill the vessel with a ratio of 71.25kg Calcite to 10-12kg (approx. 1/2 bag) of Magnesium.
  • Test your pH ongoing and add more filter media when the pH drops below the minimum desired level (ie. 6.8 pH).


Return Policy

Due to the nature of the products we sell, a strict return policy is in place. We work with food grade certified materials that must be un-opened and un-used as to be able to be re-sold.

You may receive a refund or credit of equal amount, less the restocking fee if applicable and any other deductions that are relevant.

  • Wrongly purchased items may be returned for a merchandise credit, this applies for but not limited to: Wrong size, wrong system etc.
  • 30 Day return Policy: Returns will not be accepted without prior approval or after 30 days of invoice date.
  • All returns will incur a 17.5% restocking fee or cost to send the item to you whichever greater. FSA may use discretion to determine the restocking fee.
  • Any damages (minor, that can be repaired) will incur a fee which will be deducted from the total refund which will be equal to the cost of the replacement
    parts (List Price) and labour charge (if applicable) to repair the system(s). This will be separate to the restocking fee.
  • Any damage considered to be major and not feasible for repair may be refused and the return request will be void. The customer will be responsible for the return freight or disposal of the damaged unit.
  • Return shipping is to be paid by the buyer to the address provided. It is recommended that the customer applies transit warranty to the return freight in case of damage.
  • Any damages to the system that were not reported to FSA within 48 business hours of receipted delivery are not covered under our transit warranty.

  • Should the item appear faulty or doesn’t work how described, the unit/item must be returned for testing (if requested), the return postage paid by the buyer. If the unit/item is deemed to be faulty, compensation will be provided for the postage cost (Proof of cost required). If the unit/item is deemed to be in working order and as described, the buyer will responsible for return postage.

If you have any questions about our return policy, please contact us before purchase. This will also help to ensure you purchase the correct product that suits your requirements.