The rejection water of the reverse osmosis systems is a concern for those growers who use these systems to obtain the best water quality for irrigation and can present itself as an issue for large producers. When we need large amounts of reverse osmosis water, we must know that the amount of water discarded will be at least twice as much as the water produced by the osmosis system. This is why we wanted to publish an article talking about the rejection water of the reverse osmosis systems and the different methods to minimize it and also how to re-use this water.

WHAT IS THE REJECTION WATER?

The rejection water is the waste that comes out from the reject pipe (black color) and is sent to the drain when using a reverse osmosis system. Once the tap water has passed through the sediment and carbon filters, it enters the reverse osmosis membrane, which will purify a certain amount of water and send to the drain another amount of water with the dissolved salts that we want to remove. The rejection water is a clean, chlorine-free water but with an EC between 15-20% higher than that of tap water.

REJECT THE MINIMUM AMOUNT OF WATER

Flow restrictor 400 l/min

The amount of water rejected by a reverse osmosis system will depend directly on the flow restrictor installed by the manufacturer. Many reverse osmosis systems are designed to eliminate 4:1, 5:1, 6:1 or even more. This means that for every liter of water produced, 4, 5 or 6 times more water is needed and will be sent to the drain (or garden).

GrowMax Water reverse osmosis systems are designed to reject ONLY (2:1) two liters of water for every liter of purified water. This saves a lot of water!

The more water that is rejected will have a direct effect on the life of the reverse osmosis membrane. Smaller amount of rejected water can decrease the life of the membrane.

Diagram of a reverse osmosis membrane

But in addition, two more factors must be taken into account: The EC of tap water and the inlet water pressure of the reverse osmosis system.

1 – THE EC OF TAP WATER

Reverse osmosis systems remove up to 95% of salts and heavy metals from the water, i.e. depending on the EC of the tap water, so will be the quality of the purified water.

The life of the membrane will depend directly on the EC of the tap water. The higher the EC, the life of the membrane will decrease due to the amount of salts retained. Although the positive part of this is that we will reject the minimum water quantity as possible.

2 – THE INLET WATER PRESSURE

The inlet water pressure on a Mega Grow 1000 system

Reverse osmosis membrane manufacturers recommend a minimum pressure of 4,3 Kg/cm2 (BAR) for the membrane to work in good condition. Therefore, water production will increase or decrease depending on the pressure of water entering the membrane. Insufficient water pressure will cause the system to produce less water while increasing water rejection. If we have a lower inlet water pressure than recommended, we will must to install a Pressure Pump Kit for the system to work in optimal conditions.

HOW CAN WE USE THE REJECTION WATER?

As mentioned above, the rejection water contains a higher amount of salts than the tap water. We have also commented that the reject water is sediment and chlorine-free, which will allow us to use it for other purposes. For example, by accumulating the rejection water in a tank we can use it to clean the growing rooms and cabinets, trays, pots, tools, etc. In addition, we can also use it for scrubbing floors or for water for washing up. We can also send the water to the garden, for irrigation of trees or plants that do not need a low EC water. Finally, for all those who have a swimming pool, do not hesitate to fill it with the rejection water generated by reverse osmosis system.

All those chlorine-free waters (wells, ditches, reservoirs, etc …) are susceptible to accumulating unwanted substances for irrigation: viruses, bacteria, herbicides, pesticides… Therefore, one of the questions that most concerns growers who use these types of water, it is whether they should use a UV lamp to sterilize the water, or not.

When we grow, we have several obvious reasons to maintain a pathogen and unwanted bacteria free setup. And the best way to do this is to start with a purified base water, using a Reverse Osmosis System. But there are some cases where it is necessary to add a UV lamp as a sterilizer.

In the case of using a Reverse Osmosis system or a Filtration System, it is necessary to install the UV lamp in the irrigation circuit, before these, to kill 99.99% of viruses and bacteria, thus sterilizing water. Furthermore, by installing the UV lamp before our water treatment system, we will lengthen and protect the life of the systems filters.

Ultraviolet radiation

Ultraviolet radiation or UV radiation is an electromagnetic radiation whose wavelength is approximately between 10 nm and 400 nm. Its name comes from the fact that its range starts from shorter wavelengths than what humans identify as the violet color. But this light, or wavelength, is invisible to the human eye as it is above the visible spectrum. This radiation is an integral part of the sun’s rays and produces several health effects because is between an ionizing and non-ionizing radiation.

Types of UV radiation

There are 3 types of ultraviolet radiation, according to their wavelength:

UVA: UVA radiation is the least harmful and the one that reaches Earth the most (95%), but overexposure is also harmful. Almost all UVA rays pass through the ozone layer. It is responsible for the immediate tanning of the skin. In the long term it also favors skin aging and the development of skin cancer. It is between 320 and 400 nm.

UVB: It is biologically very active but the ozone layer absorbs most of the UVB rays from the sun. However, the current deterioration of the layer increases the threat of this type of radiation. As short-term effects, it is responsible for burns and delayed tanning. In the long term, it favors skin aging and the development of skin cancer. It is between 290 and 320 nm.

UVC: It is the most harmful due to its great energy. Fortunately, oxygen and ozone in the stratosphere absorb all UVC rays, so they never reach Earth’s surface. It is between 100 and 290 nanometers.

How does a UV sterilizing lamp work?

The key factor for effective operation of a UV sterilizing lamp lies in the wavelength of the light it emits: UV-C light. With a short and powerful wavelength, it destroys nucleic acids in the DNA of a pathogen. Eliminating their ability to infect, reproduce, and perform vital cellular functions, making them harmless.

Its use is recommended in cases of using accumulation water tanks. Especially if they are exposed to the sun and the water remains stagnant for an amount of time. Even if you have used previously treated tap water, if that water will also remain stagnant for an extended period of time, there is a very high probability that unwanted pathogens will proliferate again. In both cases, the only way to ensure complete sterilization is to install the UV lamp after the accumulated water has been deposited, before the water enters the crop irrigation circuit.

For all the cases in which it is watered using a chlorine-free water, coming from wells, ditches, reservoirs or similar, GrowMax Water offers different Kits of UV sterilizing lamps: The UV Lamp Kit 4 LPM (with a flow of 4 L/min) and the UV Lamp Kit 22 LPM (with a flow of 22 L/min). Which include transformer, fittings and wall mount clips. Everything ready to install and use.

At GrowMax Water we are experts in Water Filtration Systems for Hydroponics and Gardening. To help improve your water quality or your installations, we offer you a range of “Kits” and accessories.

GrowMax Water filtration systems eliminate up to 99% of chlorine from water, while the RO systems, in addition to eliminating chlorine, also help you to lower the EC (up to 95%) and stabilize the pH. In addition you can also complement your RO systems to get ultra pure, 000ppm water by adding our De-Ionization Filter Kit. We also offer a Float Valve Kit, to avoid water overflow of your holding tank water, a UV Lamp to kill viruses and bacteria from well water, and RO Pump Kits to get more inlet water pressure, to boost production and quality.

All accessories have been designed to complement the GrowMax Water units to get you the best quality water and satisfy your growing needs.

I need more inlet water pressure for my RO unit: RO Pump Kit

The inlet water pressure is the most important factor for good operation of a reverse osmosis system. So, once you have your RO system installed, you need to check the pressure gauge to see the inlet water pressure.

According to all reverse osmosis membrane manufacturers the mínimum inlet pressure needed for a working production is 3kg/cm2 or 45psi.
All membrane manufacturers base their production calculations on 60 psi (4,3 kg/cm2) and advise that the mínimum pressure neccesary for a good operation is 45 psi (3kg/cm2) for an RO unit. That’s why with a good strong inlet pressure, RO units will produce a good quantity and good quality water, while also sending less water to drain. With a low inlet water pressure, the RO unit will not produce a good quantity and quality of water, also the drain will increase.

To avoid these problems, if after installing your RO unit the pressure gauge is under the minimum requirement (40 psi – 3 kg/cm2), you should install the RO Pump Kit for Power Grow 500 and Maxquarium 000 PPM, or the High Flow RO Pump Kit for the Mega Grow 1000 unit. These kits will increase the inlet water pressure for the membrane work in good conditions, and both include all necessary for their easy installation.

I want Ultra Pure water with any RO water system: De-Ionization Filter Kit

Using a RO system, you lower the EC from the water up to 95%, which means eliminating almost all the salts and heavy metals dissolved in the water. But if you would like an ultra pure water, of 000 ppm and 0,00 EC, then you must use a De-Ionization filter, installed after the RO.

Our Maxquarium 000 PPM reverse osmosis unit, already includes a de-ionization filter, however we also offer the possibility of installing a de-ionization filter kit after any reverse osmosis system, to achieve ultra pure water. The De-ionization Filter Kit is available in 10” and 20”, according to the flow of water you need.

The De-ionization filter contain both anion and cation resins that will eliminate 100% of the remaining salts, having already passed through the reverse osmosis membrane. This filter is replaceable and it’s recommended to change it when your EC meter shows higher levels than 0,00.

I want to avoid water overflow when I fill my holding tank: Float Valve Kit

Maybe on more than one occasion you have forgotten about the water as you were filling your tanks…. and the water overflows. This is a typical situation that has happened to more than one of us.

But you can avoid this using the GrowMax Water Float Valve Kit. This will stop the production of the Filter or RO unit, when the water reaches the Float Valve height in the tank. Thus, water overflow as well as water waste is also prevented.

I want to kill viruses and bacteria from well water: UV lamp Kit

GrowMax Water RO systems eliminate Chlorine, sediment and dissolved salts from water, providing pure and clean water. But if you are using water from an underground well, it’s very probable that this water also contains viruses and bacteria, and a good way to eliminate them is with the UV Lamp Kit.

UV lamps kill up to 99,99% viruses and bacteria from water, which especially live in well water or tanks with rain water accumulation. These bacteria can do damage to your plants, as well as doing damage to the RO membrane, causing it to fail. If you are a possible contaminated water, you should install the UV Lamp Kit before the RO system.

We offer two UV Lamp Kit models, with different flow capacity: 4 LPM (liters per minute) or 22 LPM, according to your needs.

I need more tubing for my installation: Tubing Kit

All GrowMax Water systems include a complete installation kit with a 3 meters of feed water tubing, 3 meters of product water tubing and 3 meters drain tubing.

However, some installations may require more meters of tubing, as the tap water connection or the pure water tank is far from the installed unit, or simply because the drain is an extra few meters away. For these cases we offer separate Tubing Kits – containing 10m in each.

Now you know the GrowMax Water accessories. Ask for them in your local Hydro Store and Grow Shop or contact us at grow@growmaxwater.com

We  will raffle off on Facebook a water filtration system ECO GROW 240 L/h to irrigate your plants without Chlorine, Sediment, dirt, rust, oxidation Herbicides and Pesticides and without Volatile Organic Contaminants. Thus, you will protect the plants roots from chlorine, which burn them, and the beneficial microorganisms that live in your soils.

Visit our Facebook Fan Page GrowMax Water, like us and share the image of the raffle. You will enter in the contest to win a water filtration system ECO GROW 240 L/h to discover the benefits of irrigating with water free of chemicals.

Read the complete bases here:

This promotion is in no way sponsored, endorsed or administered by, or associated with Facebook.

1. Eligibility

This Campaign is open only to those who are 18 years old or more.

2. Agreement to Rules

By participating, the contestant agree to be fully unconditionally bound by these Rules, and You represent and warrant that You meet the eligibility requirements. In addition, You are agree to accept the decisions of GrowMax Water Europe SL as final and binding as it relates to the content of this Campaign.

3. Campaign Period

Entries will be accepted online starting on Wednesday 8 th of March, and ending on monday 15th of March at 24:00h (Spanish timetable).

4. How to Enter

The Campaign must be entered by submitting an entry using the online form provided at GrowMax Water Fan page . The entry must fulfill all Campaign requirements, as specified, to be eligible to win a prize. Entries that are incomplete or do not adhere to the rules or specifications may be disqualified at the sole discretion of GrowMax Water Europe SL. Optional verbiage to include: You may enter only once. You must provide the information requested. You may not enter more times than indicated by using multiple email addresses, identities, or devices in an attempt to circumvent the rules. If You use fraudulent methods orotherwise attempt to circumvent the rules, your submission may be removed from eligibility atthe sole discretion of GrowMax Water Europe SL.

5. Prize

The Winner of the Campaign win an ECO GROW will receive a Water Filer System ECO GROW 240 L/h. No cash or other prize substitution shall be permitted except at GrowMax Water Europe SL discretion.

The prize is nontransferable. Any and all prize-related expenses, including without limitation any and all federal, state, and/or local taxes, shall be the sole responsibility of Winner. No substitution of prize or transfer/assignment of prize to others or request for the cash equivalent by Winner is permitted. Acceptance of prize constitutes permission for GrowMax Water Europe SL to use Winner’s name, likeness, and entry for purposes of advertising and trade without further compensation, unless prohibited by law.

6. Odds

The odds of winning depend on the number of eligible entries received.

7. Winner Selection and Notification

Winner will be selected in a random drawing from among all persons making purportedly valid claims for the Prize by Sortea2, under the supervision of GrowMax Water Europe SL. Winner will be notified by Facebok GrowMax Water fan page and by e-mail within the 24 hours following selection of Winner. GrowMax Water Europe SL shall have no liability for Winner’s failure to receive notices due to spam, junk e-mail or other security settings or for Winner’s provision of incorrect or otherwise non-functioning contact information.

If Winner cannot be contacted, is ineligible, fails to claim the prize within 7 days from the time award notification was sent, or fails to timely return a completed and executed declaration and release as required, the prize may be forfeited and an alternate Winner selected. Receipt by Winner of the prize offered in this Campaign is conditioned upon compliance with any and all federal, state, and local laws and regulations.

ANY VIOLATION OF THESE OFFICIAL RULES BY WINNER (at GrowMax Water Europe SL sole discretion) WILL RESULT IN WINNER’S DISQUALIFICATION AS WINNER OF THE CAMPAIGN, ANDALL PRIVILEGES AS WINNER WILL BE IMMEDIATELY TERMINATED.

8. Rights Granted by You

By entering this content You understand and agree that GrowMax Water Europe SL ,anyone acting on behalf of GrowMax Water Europe SL , and GrowMax Water Europe SL licensees, successors, and assigns, shall have the right, where permitted by law, to print, publish, broadcast, distribute, and use in any media now known or hereafter developed, in perpetuity and throughout the World, without limitation, your entry, name, portrait, picture, voice, likeness, image, statements about the Campaign, and biographical information for news, publicity, information, trade, advertising, public relations, and promotional purposes. without any further compensation, notice, review, or consent.

By entering this content, You represent and warrant that your entry is an original work of authorship, and does not violate any third party’s proprietary or intellectual property rights. If your entry infringes upon the intellectual property right of another, You will be disqualified at the sole discretion of GrowMax Water Europe SL. If the content of your entry is claimed to constitute infringement of any proprietary or intellectual proprietary rights of any third party, You shall, at your sole expense, defend or settle against such claims. You shall indemnify, defend, and hold harmless GrowMax Water Europe SL from and against any suit, proceeding, claims, liability, loss, damage, costs or expense, which GrowMax Water Europe SL may incur, suffer, or be required to pay arising out of such infringement or suspected infringement of any third party’s right.

9. Terms & Conditions

GrowMax Water Europe SL reserves the right, in its sole discretion, to cancel, terminate, modify or suspend the Campaign should virus, bug, non-authorized human intervention, fraud, or other cause beyond GrowMax Water Europe SL control corrupt or affect theadministration, security, fairness, or proper conduct of the Campaign. In such case, GrowMax Water Europe SL may select the Winner from all eligible entries received prior to and/or after (if appropriate) the action taken by GrowMax Water Europe SL. GrowMax Water Europe SL reserves the right, in its sole discretion, to disqualify any individual who tampers or attempts to tamper with the entry process or the operation of the Campaign or website or violates these Terms & Conditions. GrowMax Water Europe SL has the right, in its sole discretion, to maintain the integrity of the Campaign, to void votes for any reason, including, but not limited to: multiple entries from the same user from different IP addresses; multiple entries from the same computer in excess of that allowed by Campaign rules; or the use of bots, macros, scripts, or other technical means for entering. Any attempt by an entrant to deliberately damage any website or undermine the legitimate operation of the Campaign may be a violation of criminal and civil laws. Should such attempt be made, GrowMax Water Europe SL reserves the right to seek damages to the fullest extent permitted by law.

10. Acceptance of rules

Entering this contest supposes the full acceptance of these rules and the final results. You agree to release and hold harmless GrowMax Water Europe SL and its subsidiaries, affiliates, advertising and promotion agencies, partners, representatives, agents, successors, assigns, employees, officers, and directors from any liability, illness, injury, death, loss, litigation, claim, or damage that may occur, directly or indirectly, whether caused by negligence or not.

In this article we would like to help you to understand how a reverse osmosis membrane works. The following information is valid for all reverse osmosis membranes, supplied by GrowMax Water or other manufacturers.

A reverse osmosis membrane is made of different polyamide layers through which tap water is filtered. With this process, we obtain a water with a lower EC (with a low salt level) and free of bacteria and virus. The pores of the polyamide layers are able to filter up to 0,0001 microns.

Production specifications of the reverse osmosis membranes

The specification is made by the Membrane Manufacturers and is based on the following parameters:

1 – Water Temperature: 25º C

2 – Water Pressure: 60 psi (4.3 kg/cm3

3 – TDS (Total Dissolved Solids): 500 ppm (0.7 EC)

Therefore the production will increase or decrease according to variations in the above water conditions. Example:

-Water production will decrease by 3.6% for each degree below 25º C. So, if your water temperature is 15ºC, then; 10º (less) x 3.6% = 36% decrease. Now, 20 L/h can be about 13 L/h.

-If the temperature is even lower, let’s say 10ºC, then: 15º (less) x 3.6% = 54% decrease. 20 L/h can now be as low as 9 L/h.
-Also, at the same time if the inlet pressure is lower than 60 psi (4,3 kg) then your production will also decrease.
-Also if the TDS is higher than 500 ppm (EC higher than 0.7), then again, you will have another lower production rate. The higher the EC, more inlet water pressure is needed.

How long will a membrane last?

We cannot know exactly how long a reverse osmosis membrane will last, because it depends on three factors:

1- The quality of the water
2- The amount of water passing thru
3- The amount of waste water.

For example, the higher the EC, the worse is the quality water filtered, means the membrane can sooner be incrusted with salts. The higher the amount of water filtered, the less is the life of the membrane, and the same happens because of the amount of waste water, that is to say, the less waste water amount the sooner the membrane will be full of salts. This last point is very important, so we will explain it in more detail below.

The waste water in RO systems

All the reverse osmosis systems must send waste water to the drain. Why? The different polyamide layers of the membrane retain the salts from the water, but that portion of the water doesn’t go to the drain needs to be flushed out of the membrane, so that the membrane doesn’t become incrusted with those salts.

GrowMax has designed its reverse osmosis systems for the Hydroponic and Gardening markets. Because we are not using pressurized holding tanks, different from residential RO units, we have designed our units to REJECT MUCH LESS water than others conventional units.

Most RO systems are designed to reject 4:1, 5:1, 6:1 or more. This means for each liter of water produced, 4, 5 or 6 times of the amount of water is needed and send it to the drain (or garden). GrowMax units are designed to reject only 2:1. This saves a lot of water.

However, the downside to this design is that if the TDS or EC is very high, more than 500 ppm (> 0.7 EC) then the lifespan of the reverse osmosis membrane can be diminished.

GrowMax Water reverse osmosis systems use 150 GPD (Gallon per Day) membranes for the POWER GROW, MEGA GROW and MAXQUARIUM.

This is the highest production membrane currently available in this size and configuration, without using much higher cost membranes that require much higher inlet pressures, pumps and motors.

Reverse osmosis membrane diagram:

Accessories to improve the reverse osmosis membrane

GrowMax offers solutions to improve your installation or help in the case of adverse water conditions. These solutions are different accessories that will help you to boost the membrane production:
– If your inlet water pressure is low (less than 40psi/3 kg), you have to install a GrowMax Water Booster Pump to your RO system. This will increase the water pressure to a 4-5 kg constant inlet water pressure. We have a Booster Pump Kit valid for use with POWER GROW and MAXQUARIUM and also a High Flow Booster Pump Kit, valid for use with the MEGA GROW.

– In case your water has a high EC level, the membrane can be saturated and clogged sooner. You can change out the FLOW RESTRICTOR in your unit, to a larger flow restrictor, to allow for more water rejection to the drain, thus helping to prolong the life of your membrane.

POWER GROW 400ml 550ml (foto)
MEGA GROW 550 ml 800ml (foto)
MAXQUARIUM 400 ml 550ml (foto)

Learn more about GrowMax Water Reverse Osmosis Systems designed for hydroponics and gardening.

How many times have you forgotten to turn off the water before the water tank reaches its maximum capacity?

While we wait to full our tank of purified water, we often prepare fertilizers and nutrients or focus on other issues like cleaning the grow room or even leaving for a while. However, after a long absence, we may come back to find a mess in the grow room: the water overflows and the room is flooded.

This is a very common situation that has happened to more than one of us, but this can be prevented by installing a float valve in the tank.

How does the float valve work?

Commonly known as float buoy, when the water reaches the top of the float valve, it stops the system and so the water production. Thus, water overflow as well as water waste is prevented.

The Float Valve controls the water level we need in the tank according to our irrigation needs. Now we can mix in in our tank the nutrients and fertilizers we need to water our plants till we obtain the necessary EC level without wasting any water.

Installing this equipment is very easy and will help us to prevent more than one surprise in our grow room. Growmax Water offers the Float Valve Kit  which includes all the connectors to be easily installed.

“Forget about wasting water and time cleaning a flooded floor”

Find more information about GrowMax accessories available in our website or contact us through our costumer service.

A good maintenance of Reverse Osmosis and Filtration systems will always guarantee the best water quality. For this reason, knowing when to replace the filters will help you to ensure your system will maintain optimum performance and reliable service for many years.

All GrowMax Water Filtration and Reverse Osmosis systems include high capacity green coconut carbon block filters. These ECO Friendly Filters utilize high performance coconut shell carbon that is manufactured using a patented process that significantly reduces harmful green house gas emissions. They also have superior absorption capabilities compared to other types of carbon, having more micro-pores and a unique binder system delivering a product with superior absorption capacity and kinetic dynamics. So GrowMax Water filters are not only better performing than anything on the market, but also good for the Earth.

When to replace the filters in your Filtration Systems

Filtration systems are the best option to eliminate chlorine, herbicides, pesticides and volatile organic contaminants. All GrowMax Water systems have a 5 micron sediments cartridge that reduces dirt, sand and rust, and a high capacity carbon block filter to eliminate up to 99% of chlorine.

To best guarantee that chlorine and other contaminants are eliminated from the water efficiently, you must replace filters before they arrive to their maximum absorption capability. If you don’t replace in a timely manner, filters can become saturated and will not absorb anymore chlorine. To avoid this problem, it is recommended to change filters regularly, according to the unit capacity and water use, following instructions we give you in this table.

You can purchase GrowMax replacement filters in your local shop or we can refer you from the Growmax Water website. Replacement filter packs contain 1 – 5 micron sediment filter and 1 high capacity carbon block filter.

When to replace Reverse Osmosis filters

If in addition to eliminating chlorine you want to lower the EC of your water, eliminating salts and heavy metals, then you need a GrowMax Water reverse osmosis system, the best way to get pure water.

In reverse osmosis systems you must keep in mind that more water passes thru the carbon block filter and so the importance of replacing the carbon block filters on time is higher than in the filtration systems. If the carbon block cartridge doesn’t absorb the chlorine, this chemical will arrive to the membrane and will eat away at the membrane material. If this happens, you not only will need to change the filters, but also the membrane.

Here  you can check when to replace the reverse osmosis filters, according to the water use and your GrowMax Water unit capacity. You can also visit our website to get more information about where to buy replacement filters, or ask at your local shop.

How to change the filters

It’s very easy to replace filters in GrowMax Water systems, as we show you in these tutorial videos, with all the steps you must follow:

Replace Filtration systems filters:

Replace Reverse Osmosis filters:

GROW IT TO THE MAX, WITH GROWMAX WATER!

The first thing we need to know when installing a reverse osmosis System is the inlet water pressure.

All membrane manufacturers base their production calculations on 60 psi(4,3 kg/cm2) and advise in most cases a mínimum pressure neccesary of 40 psi (3kg/cm2) for the RO unit to function correctly.

Importance of a good strong inlet pressure

With a good strong inlet pressure, RO units will produce a good quantity and good quality water, while also sending less water to drain.

Without a correct water pressure (less than 40psi/3kg) Ro units will produce less water, worse quality and also send more water to the drain.

For this reason, all Growmax Water Garden Reverse Osmosis Systems include a pre-pressure gauge, pre-installed after the sediment prefilter and before the green carbon block pre-filtre and in all cases, before the membrane.

How to obtain the best results with your RO unit

If after installing the RO unit you see the pressure gauge below the mínimum requirement (40psi/3kg), you shoould install a Growmax RO Pressure Pump Kit, to obtain best results for quantity and quality of water. This Pump kit will raise your inlet water pressure by 40psi/3kg. Above your corrent inlet watwer pressure.

GrowMax Water has two Pump Kits available, the first for the Power Grow and Maxquarium units, then also a HF (High Flow) Pump to be used with the higher producing Mega Grow unit.

Remember that good, strong water pressure is the key to an optimum functioning RO unit.