Float valve for tanks: the solution to prevent water overflow

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.

Are you ready for the new season of indoor growing?

Autumn is here and we start a new season of indoor growing. It’s time to prepare our grow room and review all the indispensable accessories to get the best results. A Water Filtration unit or Reverse Osmosis system is the first accessory you will need to get the best quality water for growing

As a house must be built with a good and strong foundation, you must also start with pure water to have a strong foundation for growth. A clean, free of chlorine and low EC water, is the right way to help our plants grow to their full potential. Just us we keep in mind the nutrients and fertilizers we are going to use, is also important prepare the water before we start to irrigate our plants.

Water quality control in indoor growing

With indoor growing we can control the light hours, the temperature and humidity in the room according with the plant’s needs and we can even control the water quality that we will use to irrigate them. There are different accessories for this that must be in our indoor room: the EC meter, for measuring the quantity of dissolved mineral salts are in the water (but which doesn’t tell us the quantity of each salt component), and a pH meter, very important to control the pH levels.

osmosis inversa en cultivo de interiorThese water treatment systems and control accessories are very helpful for growing, because water is not the same everywhere. We can receive soft water (low EC) or hard water (high EC), according on the amount of mineral salts we have in our tap water. Hard water contains a high level of dissolved salts, that will directly influence the quantity of nutrients we need to add to the water we give to our plants.

-Keep in mind that our plants can receive an EC of up to 1,4 to 2,2, according to its genetics and depending on the growing stage. The higher the EC level is, less nutrients we can give to our plants. Here an example:

“If the water we use has an EC of 1,0 then we will only be able to add from 0,4 to 1,2 of nutrients to reach our maximum levels. If on the other hand, we start with an EC in the water of only 0,1 or 0,2 or even an EC of 0,0 then we will be able to add much more nutrients to our plants.”

– Less nutrients we can add, more risk for deficiencies in our plants, like deformed leaves or with yellow and brown spots because of a lack of calcium ; yellow leaves because of the lack of magnesium, among other problems.

-With a high EC level, the water will have high levels of calcium, and will cause lime scale in the roots, decreasing its absorption capability.

-If we irrigate with hard water and then we add even more nutrients to our soil, we can cause a nutrient lockout , that can inhibit the growth of our plants.

Reverse osmosis systems eliminate up to 95% of all dissolved salts, lowering the EC, getting pure water. They also eliminate heavy metals and chlorine up to 99%. Also, reverse osmosis helps to stabilize the pH, between 6 and 6,5.

“Using reverse osmosis you will get clean, pure, quality water for growing to the max indoors.”


However, even if the water from the tap doesn’t have high EC levels, chlorine will be the enemy, because as we all know, it is a chemical that attacks plants roots, burning them, while also killing off beneficial micro-organisms (link to the article) whom live in our fertilizers.

Water Filtration Systems are the solution to eliminate chlorine up to 99% and also reducing sediment, rust and oxidation. These systems also eliminate Herbicides, Pesticides and Volatile Organic Contaminants that also affects the plants.

In summary, if you are preparing your indoor room with indispensable accessories for the new growing season, remember to include a water treatment system (link). Together with the EC meter and pH meter, you will achieve clean, quality water that your plants deserve.

Grow it to the MAX this indoor season, with GrowMax Water!

When to replace the filters in your water systems

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

water filtersFiltration 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

reverse osmosisIf 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:



Calcium and magnesium: two important nutrients for our plants

When growing plants there are two important nutrients that often we forget: calcium and magnesium. If we provide plants correct doses of both nutrients, we get better results.

Calcium builds strong stems and leaves. When calcium is taken up by the plant it forms pectin, the glue that binds cell walls together, so a steady supply of calcium is necessary throughout the plants life cycle to strengthen its vascular system. If the plant has a healthy vascular system, it is also able to take up water and all the other essential minerals more efficiently, resulting in a stronger, more disease –resistant plant.

Maintaining adequate levels of magnesium throughout the crop cycle is also essential. Magnesium is the central element in chlorophyll, essential for absorbing light energy and converting it to high-energy sugars. Magnesium also activates more than 300 known enzymes in plant cells, including the enzymes that load sugars for transport throughout the plant. It is especially important when the energy need of the plant are highest, such as during periods of rapid vegetative growth or during heavy fruiting and flowering.

When plants are suffering a deficiency of either of these two nutrients, there are some symptoms that appear in plants. A Calcium deficiency normally shows up in new growth at the growing tips of the plant, causing deformed leaves and reduced root growth. If there is a magnesium deficiency, part of the leaves will turn yellow, because of the lack of chlorophyll, the green pigment in plant leaves and the central element of magnesium. Magnesium deficiencies are fairly common in indoor gardens, due to the powerful HID grow lamps that indoor gardeners often use. As the light become more intense, plants need more magnesium to efficiently use the light energy.

Calcium and magnesium supplements for plants

calcio y magnesioThere are different kinds of calcium and magnesium supplements for our plants. If we add these products, we will give plants the nutrients they need for growing healthier and to the max. Calcium and magnesium supplements may be derived from carbonates, nitrates or sulfates, and it can be added in standard concentrates, powdered supplements or organic supplements.

It is important to be careful with supplements derived from nitrates during flowering, because an excess of nitrates during this stage may delay or event prevent flowering. That’s what happens with standard concentrates, derived from nitrates.

Calcium and magnesium are 98% water soluble and available to the plant, just make sure the powdered supplement is thoroughly diluted with water and mixed well. They should be added to water before any other fertilizers or additives. Powdered supplements contain some nitrates, but not nearly as much as liquid concentrates.

Organic supplements are derived from calcium carbonate and magnesium carbonate. One of the benefits of calcium and magnesium carbonate is that they contain no nitrate. Therefore, it won’t interfere with flowering. The down side of going organic is that calcium and magnesium carbonate are only sparingly soluble, so in some ways, organic calcium and magnesium may actually change clean water into hard water. The result is the potential for limescale in the root stem. To avoid this, if you choose to use an organic calcium or magnesium product, always use an amino acid supplement with it.

However, added high doses of calcium and magnesium supplements can cause deficiencies too in our plants, like limescale in the root stem, damaging roots and avoiding the plant capacity to absorb necessary nutrients. So it’s important to quantify the doses of nutrients we added to our plants, according to the type of plant or growing stage.

Saturation of calcium and magnesium happens when we add these supplements to water without knowing the exact doses of calcium and magnesium that our water already contains. We can use our EC meter to measure the total quantity of dissolved mineral salts in our water but that still will not tell us what the percentage of calcium and magnesium are.

To simplify this process, most growers prefer to use Reverse Osmosis water (RO). That way, they can start to irrigate with pure water (0,0 EC), without dissolved salts, that means without calcium and magnesium. By starting with pure water, growers can then add the exact quantities of nutrients and supplements their plants really need. Learn more about reverse osmosis.

Grow it to the Max, with GrowMax Water!   

Tricks to irrigate plants during holiday

Summer is here and it’s time to take a deserved break. It’s time to pack your bags and go to the beach, to the mountains or, ultimately, anywhere without stress. But, what we do with our plants if no one can water them while we are off? There are a few tricks for watering plants while we are gone that keep them hydrated until we come back.

We must avoid our plants dying and try to keep our plants as healthy as we do during the rest of the year. One easy solution would be to ask a friend or neighbor to irrigate them twice a week, but during holidays it’s difficult. If we go on holiday for a short time (a week) we can prepare the plants and keep them ready until our return. If we are planning a longer trip, there are also some tricks to prevent lack of water in our plants.

Prepare our plants before we go

If we are going to be away of home only for a week, we can leave them without any irrigation system. However, it’s important to follow some advice before we leave so that upon our return home we see little damage in plants and they are easy to fix with our usual care.

First of all, we have to water them well before leaving to maintain the maximum humidity for as many days as possible, but without flooding the plants and also never put them into a bowl full of water directly in contact with roots, because they will rot.

We have to put the plants in a cool place where sun and heat don’t affect them constantly. This way, they will benefit more from the environmental humidity and they won’t get sun dried. If you have indoor plants, you must put them in a room with dim light and some ventilation.

If we cut back the biggest leaves, dry leaves and branches before going on holidays, it will also help our plants to keep better humidity and they will be stronger without constant water.

Automatic systems to irrigate

apsersorjpgIf we stay away of home for more days, we have to find alternatives to irrigate the plants. But also following the steps explained in the previous paragraphs before leaving. If we have outdoor plants in our garden or terrace, it will be useful to install automatic irrigation systems.

A sprinkler system or drip irrigation installation in the garden or terrace will allow us to program watering for all the plants during our absence. They are also useful during the year. But if we don’t have the budget, or they are indoor plants or in a balcony, we can use home remedies that will help to maintain plants hydrated.

Homemade systems to irrigate plants

botellaWe can easily create a watering system with a plastic bottle. It consists of a drip irrigation system that will provide constant water to plants but without flooding them. We have to open a hole in the cap (just as big as a water drop), fill up the bottle and put it upside down, staked in the soil of the pot, and the water will be provided gradually to the plants roots. The bigger the bottle, the more water that will be provided.

We have to put one bottle in each pot or near each plant, so we guarantee all the plants will have enough water and will be hydrated during our absence.

There is a similar homemade system, but using little clay cones. They are dispensers that we have to screw in the bottle, and then stake in the soil with the bottle upside down. As in the previous system, water will be provided to the plant drip to drip, but there is a difference: the clay. This material has microporous qualities that guarantee that water will be better dosed.

Plants always need quality water

With these tricks to irrigate plants during our holiday, we avoid problems caused by lack of water. In summer, plants suffer more problems due to high temperatures, so irrigating them when we are off  on holiday is important for taking care of them. However, water quality, water without chlorine, is also very important for their care. That’s why we shouldn’t forget to always use clean water, treated by filtration systems. These systems can also connect directly with the installations of automatic irrigation systems.

Now we can pack our bags and start a happy holiday, knowing that our plants will be well hydrated and healthy for the days or weeks that we will be gone.

The effects of beneficial micro-organisms in plants

Beneficial microorganisms are a vital part of the soil and, consequently, an important part of plants food. They are also an essential part of organic composts. But there is an enemy of these micro-organisms: chlorine.

These micro-organisms are very important for the soil food web. They are micro, but they have a big function in the soil, because they directly affect the plants food, breaking down organic matter and converting it into a form that is readily available to plants. We not only find beneficial micro-organisms in forests or gardens, but also in substrates, soils and composts we use for potted soil and growing at home.

Bacteria and Fungi in plants

Bacteria and fungi are two kinds of beneficial soil micro-organisms we find living near plants to feed from their green matter. At the same time, they help plants to achieve the food they need, into a form readily available for them.

efectos microorganismos beneficiosos plantasBacteria are the oldest, most primitive forms of life and come in three styles or shapes: spiral, coccus and rod-shaped. In nature, bacteria serve as one of the main decomposers of organic matter, second only to fungi, making them a vital part of the soil food web. As they decompose organic matter, the bacteria ingest organic carbon compounds, nitrogen and any other elemental nutrients present. When the bacteria dies, all these nutrients are held in the soil. The process by which the nutrients are converted into plant-accessible forms is called mineralization.

Another example of beneficial micro-organisms are mycorrhizae, a type of fungi that growers include in composts to protect plants roots from diseases that can affect them, and to guarantee a better absorption of nutrients. In nature, these kind of fungi and plants have a mutually beneficial relationship, because they help each other to get food.

Beneficial micro-organisms are also used for avoiding parasites and other pests. By using specialized micro-organisms, like Bacilus Thuringiensis to kill worms, we can protect our plants from different parasites that affect their growth and health.

Organic compost and beneficial micro-organisms

Growers know about the importance of nutrients for the plants. A good soil is one of the basis for the plants growth and for this reason they use quality composts and fertilizers to stimulate the soil.

Beneficial micro-organisms are an important part of organic fertilizers. They improve the soil, and allow the beneficial micro-organisms to easily convert the organic matter into food available to plants.

Chlorine, the enemy

However, even with the positive effects that these micro-organisms have, there is an enemy for them: Chlorine, and especially in summer. All municipal water supplies contain chlorine, a chemical disinfectant used to kill off deadly bacteria and virus in the water supply. With hot weather, there are more possibilities of bacteria and virus, so the levels of chlorine in the water are even higher.

As chlorine is used to eliminate bacteria from water that can affect the human body, irrigating with chlorinated water can also kill the beneficial micro-organisms that live in the soil near plants, and that we find in every potting soil.

Eliminating chlorine from your water is the best way to maintain the effects of beneficial micro-organisms in our plants. 

How to avoid a nutrient lockout

A high EC water may contain larger quantities of hard water minerals, like calcium and magnesium, also known as limescale. High amounts of these minerals, together with added doses of nutrients, can block or saturate plants roots, prohibiting them from absorbing the added nutrients, which is also known as “nutrient lock out”.

As a result of this nutrient excess, plants could be damaged. Some symptoms of saturated roots are yellow, dry leaves or stunted growth, and even plants death, because they can’t absorb the nutrients they need.

Of course calcium and magnesium are necessary for growing, but in adequate quantities according to the plant needs. These minerals are nutrients for plants, and we find them dissolved in water, but we can’t know the exact amount that is present. We can use our EC meter to measure the total quantity of dissolved mineral salts in our water, but that still will not tell us what is the percentage of calcium and magnesium.

To avoid these problems, most growers prefer to start to irrigate with pure and clean water. This way, they know the exact amount of nutrients they are adding to their plants.

It’s very important, because our plants can receive an EC of nutrients from 1,4 up to 2,2, according to the type of plant or the growing stage. For example, if the water we use has an EC of 1,0 then we will only be able to add from 0,4 to 1,2 of nutrients to reach our maximum levels. Starting with an EC in the water of only 0,1 or 0,2 or even an EC of 0,0 we will be able to add much more nutrients to our plants

The best way to achieve clean and pure water is by using Reverse Osmosis systems (RO), specifically designed for use in hydroponics and gardening, because your water will be free of all salts and heavy metals up to 95%, and free of chlorine and other contaminants up to 99%.

Water hardness

Water quality and water hardness varies all over Europe, from Country to Country and even from city to city, town to town. It is important to convert hard water into soft water to be able irrigate your plants with the best quality water possible.

What is hard water? Water that concentrates a high volume of dissolved mineral salts, especially calcium and magnesium. The hardness is measured in milligrams of calcium carbonate per liter (mg /l). Depending on the concentration of magnesium and calcium in the water, we can talk about four types of water:

  • Soft water (concentration of less than 150 mg / L of calcium carbonate)

  • Semi Soft water (concentration between 150-200 mg / L calcium carbonate)

  • Hard water (concentration between 200 and 400 mg / l of calcium carbonate)

  • Very hard water (concentration between 400 and 550 mg / l of calcium carbonate.

Hard water can produce problems in the plants, like limescale precipitated in the root stem. When this happens, the plant cannot absorb the necessary nutrients, so if you add doses of nutrient solutions to the plant, they won’t have any effect on it. Moreover, if you want to add nutrient solutions of calcium and magnesium, you have to be careful with hard water, because you can cause a Nutrient Lock out: high amounts of these minerals in water, together with added doses of nutrients, can BLOCK or saturate plants roots, prohibiting them from absorbing the added nutrients.

Depending where you live, the water you receive at home has different dissolved salt levels. Living near mountains, near the sea or big cities are factors that affect the water quality. For example, take a look to this map of the water hardness at British islands:

hardness water in british islands

London area has hard water, while Edinburgh appears as a soft water area. The most important thing is that wherever you live, you can improve the water quality, lower the EC level and change it into soft water. If you irrigate your plants with the best water quality, they will be healthier and faster growing. And this process is possible with RO systems.

Reverse osmosis (RO) to lower EC

A high amount of calcium and magnesium in the water we are using to irrigate can cause deficiencies in our plants. The only reliable way to remove dissolved salts in the water, or what is the same, lower the EC, is a Reverse Osmosis System.

What are the benefits of lower EC? First of all, you will get plants with healthier and stronger roots that absorb 100% of all the nutrients you add, avoiding dissolved mineral salt accumulation in the roots, such as limescale. You will guarantee more food for your plants, because when your water EC levels are low or even 0.0 (pure water) you can add the nutrients the plants really need, without worries about excess or lack of nutrients. Fertilizers you add will also be more effective, and ultimately, your plants will grow better and healthier, which means better results and therefore better quality and more profits.

GrowMax Water has designed a complete range of Reverse Osmosis Systems for hydroponics, starting at 20 L/h of pure water, and designed to minimize the waste water, with only (aprox.) a 2:1 (bad/good) ratio. All units include an installation kit for easy connection indoors or outdoor. These systems reduce up to 95% of dissolved salts in your water, lowering the EC in addition to removing chlorine.

Converting your hard water into pure water will provide your plants the quality water they deserve. Visit our website and take a look of the range of reverse osmosis systems, and discover which one best suits your needs irrigation.