IWS (intelliegent watering system's) Guide
I found some info on IWS(intelliegent watering system's)and thought i'd use it to create a thread (that hopefully helps somebody out in some way)
So here goes...
IWS Flood & Drain Systems
Flood and drain is an irrigation technique that fills the pot with nutrient solution from the bottom. As the nutrient solution rises in the pot it forces out the air and saturates the growing media. As the nutrient solution drains from the pot, fresh air is pulled back into the growing media enriching it with oxygen - vital for healthy root growth. Frequent flooding and draining of the pot should occur in order to optimise the available oxygen in the root zone.
Here we will try to give you advice on all aspects of using the system, giving you a better chance of success.
IWS Dripper Systems
With a dripper system each pot is fed separately from the nutrient tank, via a dripper assembly which is connected to the brain.
This system is used mainly as a run to waste system rather than a recycling system.
When feeding with a dripper system you should make sure that on each feed there is a 20% run off allowing the medium to flush on every feed.
One Pot DWC
Deep water culture is a method of growing which leaves your plant’s root submerged in oxygenated nutrient solution.
The pots are connected to a control unit which will drain and refill the pots periodically. The control unit is connected to a reservoir, where the nutrient solution is stored.
The system is controlled by magnetic float-switches which regulate the fill level in each pot, ensuring that the system does not overfill. An air pump supplies oxygen to each pot individually via an air-stone located in the bottom of each pot.
Deep water culture is a method of growing which leaves your plant’s root submerged in oxygenated nutrient solution.
The IWS DWC oxygenated pot is one of the simplest and best value routes into hydroponics available. The pot is filled with nutrient solution which is oxygenated constantly by an air pump. The pots are not connected together which means that each pot works independently from any others, meaning that each pot must be maintained individually.
More and more users are reverting to hand-watering as cost becomes an issue, for this reason IWS have gone back to basics with their latest system, the HWS.
Hand-watering is arguably the purest and simplest way to grow, making it ideal for novices. The system can be run as independent pots though it works much better when connected together into a system with a control unit.
Available in 3 sizes 10 ltr – 16 ltr and 25 ltr , the HWS can be tailored to suit most users.
Flood & Drain Pro
Flood and drain is an irrigation technique that fills the pot with nutrient solution from the bottom. As the nutrient solution rises in the pot it forces out the air and saturates the growing media. As the nutrient solution drains from the pot, fresh air is pulled back into the growing media enriching it with oxygen – vital for healthy root growth. Frequent flooding and draining of the pot should occur in order to optimise the available oxygen in the root zone.
Why Pro Systems?
The IWS pro system has been designed with the grower in mind and came about due to the growing feedback from our customers. They wanted systems that could handle over 80 pots and which would fill and drain quicker. The Pro system will fill a 48 pot system in less than 10 minutes and drains back twice as quick as the standard system.
We use a high pressure pump to fill the brain bucket and twenty five millimetre pipe from the brain to the pots which allows the system to flood very quickly. We also have two brain pumps in the brain bucket which drains the systems quicker.
What Growing Media
This common question really has with no correct answer as the growing media you choose to use often comes down to personal preference. Good results can be achieved with many different media’s and mixes but the key features you should look for in your media are:
•Low-medium Water Holding Capacity (WHC)
•High Air Filled Porosity (AFP)
(i use jiffy pads to start the seed/cuttin of,that then goes in a 4" inch rockwool block then that goes in the pot's with clay stone's)
Expanding Clay Pebble's
A growing media that is ideal for flood and drain without the need for anything to be added or mixed in is Jongkind Clay Pebbles. These pebbles carry the RHP stamp and are made specifically for horticulture; they have a high rate of water retention compared to most other clay pebbles. There is plenty of air space between the pebbles creating a high AFP.
They also are capable of absorbing and releasing nutrient solution from their porous structure. Clay pebbles can be flooded frequently with a low risk of over watering, which helps keep the root zone replenished with lots of oxygen and fresh nutrients.
Did you know – A 10L pot of dry clay pebbles can absorb up to 5L of water! This shows just how porous they actually are.
Coco/Clay Pebble Mix
It is also possible to use a mix Coir (Coco) with clay pebbles to increase the WHC. When mixing coir into clay pebbles it should make up 25-40% of the total volume of the growing media. Adding coir will allow more time between floods, meaning fewer floods each day.
The IWS is very adaptable and can be run using many different growing mediums. Just remember to adopt a different flood time with each medium dependent on it’s water retention capacity.
Understanding the Flood Cycle
To get the best possible results from your IWS Flood and Drain system you must ensure you get the flood cycle right. The flood cycle is made up of 3 elements;
•Flood Frequency - This is how often you flood the pot, which largely depends on what type of growing media you’re using and how well established your plants are.
•Flood Height - This is how high the water goes up the pot. Generally we recommend you always flood to the maximum height.
•Flood Duration – This is the total time of each flood and will depend on the size of your system and your choice of growing media.
These all play an important role together in getting the irrigation strategy as accurate as possible.
This guide can be followed for all growing media, not just clay pebbles, and should provide accurate flood times and optimum results.
When you have put the system together it’s time to get the growing media prepared.
Please note: No matter what growing media you use in your pots you must use 5-10cm (2-4 inches) of clay pebbles in the bottom of the inner pots. This will help prevent the bottom from holding too much water.
Wash the clay pebbles thoroughly to remove the dust and small particles; this can be done with tap water.
Insert the root control disk into your inner pot copper side up, add enough clay pebbles to cover the bottom of the pot, then add your chosen growing media on top. Only fill the pots three quarters full with your growing media at this point.
Now fill the reservoir with water and add nutrients to a suitable strength, this should be slightly higher (2 CF units, 0.2 EC) than your plants have been getting during propagation.
Finally adjust the pH in the nutrient tank to 5.5 - 6.5.
Setting The Flood Height
Now the nutrient solution is ready, turn on the timer and start a flood cycle. Make sure the feed-duration dial is turned all the way to the right for the longest possible flood time. The brain pot will start to fill and so will the pots. As the solution slowly fills the pots the growing media will take in the pH balanced nutrient solution preparing the growing media for planting.
Your aim here is for the maximum flood height to be the same as the amount of growing media in the pot. You should be able to see the water level rising to the surface of the growing media. Check by lightly pushing down on the media surface with the palm of your hand, this will make sure the media isn’t floating up. If the water rises over the surface of the growing media add more media until the level of the nutrient solution and the growing media is the same. When the brain stops filling and all the pots have the right amount of growing media and nutrient solution, leave them soaking in the nutrient solution for at least 1 hour.
After the pre-soak period, initiate the drain cycle on the timer by turning the duration dial to the left, this cancels the feed. Once the drain cycle is finished, check the pH and nutrient strength in the reservoir. The pH may have changed so adjust if necessary. If the pH or nutrient strength has changed dramatically, empty the reservoir and change the nutrient solution.
Now you need to get a stopwatch ready to time the flood cycle. Start the flood cycle and the stopwatch (you are timing how long it takes for the ALL THE POTS to fill back to the maximum flood height). As soon as the maximum flood height is reached in all the pots stop the stopwatch and start the drain cycle.
With the time recorded you can now set an accurate flood duration on your IWS system. If you are using clay pebbles, add 1-2 minutes onto the time recorded on your stopwatch. This short period at the end of the flood, in which the pots stay filled, helps to saturate the clay pebbles and purge the pebble’s inner core and outer shell of old nutrients. It will also allow the clay pebbles at the top of the pot to draw up water and nutrients by capillary action. It is not recommended that you hold your flood height for longer than 5 minutes as leaving your plants roots completely submerged in water for too long can cause poor root function and invite disease.
If you are using a mix with coco coir then the time recorded is your actual flood time. You do not need to add any extra time as your growing media has a fast capillary action and holds more water than pebbles alone.
Your pots should still be around three quarters full with the growing media at the same depth as the maximum flood height.
When it comes to planting your young plants you should plant them 1-2 cm into the growing media at the maximum flood height. This will mean that during a flood cycle the flood height will reach the bottom of the propagation block.
Please note: If you plant your young plants too deep in the pot your propagation block will become saturated causing poor initial root growth.
Once you are happy with the planting depth, fill the rest of the pot with more prepared growing media.
Setting The Flood Frequency
How often you flood the pots will be determined by:
•The growing media.
•The plant size and water requirements.
•The environmental conditions.
The Growing Media
If you are using a growing media that does not retain much water, such as clay pebbles, you will have to flood the pots with a higher frequency. When using clay pebble and coir mixes the WHC will be higher so flood frequency will be reduced.
Flood Frequency with Clay Pebbles
After conducting our own trials 8-16mm clay pebbles now come with our highest recommendation as the best growing media for flood and drain. We recommend using Grodan 3” or 4” blocks for preparing your plants to grow in clay pebbles.
When using clay pebbles you must use the IWS ‘Aqua Pots’, these are large net pots that allow better flooding and enhanced root development. To prevent roots from ‘chasing’ the water through the drain pipe, a copper root-control disk is used in the bottom.
During a flood cycle with clay pebbles the pots will fill and drain quickly, also between cycles the pebbles can’t hold onto large volumes of water. For this reason the flood frequency can reach a maximum of 1 flood every 2-3 hours when the plant is in full vigorous growth.
Your starting irrigation frequency depends on a number of factors; the size of your propagation block, the size of your plant and your grow room environment. Remember; your propagation environment will be quite different to your grow room environment, most growers find on moving their plants into their grow room their water demand will increase due to higher temperatures and lower relative humidity (RH). It is important to make sure the block and clay pebbles are not drying too much, or staying too wet, between irrigations.
When you can see a noticeable increase in vegetative growth you can increase the frequency to once every 3-4 hours. As the plants get bigger and their demand for water increases you should adjust the frequency to once every 3 hours but remember to leave the time it take to drain back before you feed again. I.E. if you want to feed every 3 hrs wait until your drain cycle has finished before counting down to your 3 hour feeds. A lot of growers leave this as their maximum flood frequency but some large plants in a hot and dry environment with a high water demand may benefit from a flood frequency of once an hour.
Remember that during each flood, water and nutrients are delivered to your plant and on each drain oxygen is pulled into the air spaces in the root zone. Therefore when plants have fully established within the clay pebbles; more frequent floods mean more fresh oxygen around the roots. Please note: if your plants are not well established within the clay pebbles they will not benefit from frequent floods.
Setting The Frequency with Coir
When using coir and clay pebble mixes, you must use the IWS ‘Culture Pots’. These pots have a net base which has been designed specifically for finer growing media. The bottom portion of the net pot should be filled with just clay pebbles. The rest of the solid pot should be filled with your mix of coir and clay pebbles.
The key to using coir in flood and drain systems is to not over-water. For the first 1-2 weeks after planting, the establishment time, your pots will need irrigating a maximum of once a day. This flood should be in the middle of your light period. Some growers find they get better results by hand watering from the top of the pot every 1-2 days for the first week and go onto using the flood and drain irrigation cycle once they know the plants roots are well established and ready for regular irrigations. This is an excellent approach for establishing your plants, but understandably is sometimes impractical for growers with larger systems or for growers who run their light cycle during the night.
After the plants have established and vigorous vegetative growth has started, the plant’s water demand will increase. Around this time check the moisture level of your mix before the irrigation or toward the end of your light cycle, if it is drying you should increase your frequency to 2 times a day. The first and second irrigation should be equally spaced e.g. if your using an 18hr light cycle your irrigations should be at 6 and 12 hours.
These 2 irrigations are, in most cases, as much as they need, but plants that need to satisfy a high water demand may need irrigating 3 times a day during peak growth. An important phrase to remember when irrigating your coco coir and clay pebble mix is ‘transpiration before irrigation’, this means to wait for your plants to start using the remaining water in the growing media before giving them anymore. With this in mind you should have your first irrigation at least 1-2 hours after the lights turn on.
Hint: In most circumstances it is only necessary to flood the pots while the lights are on. Only during warm dark periods should you consider have 1 night time irrigation.
As with any hydroponic system, your nutrient strength and irrigation should reflect your grow room environment. For example; if the growing media is clay pebbles and during summer the room runs at 31°C with an RH of 45%, these hot and dry conditions will cause the plant to use more water and less nutrient. Consequently the nutrient strength should be set lower than usual to account for the nutrient strength rising in the reservoir. In these conditions the pots should be flooded once an hour.
In the same room during winter the room runs at 26°C with an RH of 60%, these more favourable conditions, that aren’t putting environmental pressures on the plants, will mean higher nutrient strengths can be used and flood frequencies can be reduced to once every 2 - 3 hours. It is therefore extremely important to consider the effect that your grow room environment will have on your plants and adjust your feeding strategy accordingly.
Avoiding Root Blockages
Because the flood and drain system fills and empties through the same tube, roots growing out of the pot can sometimes cause blockages in the feed-pipe. To avoid this you should always use the copper root control disks provided. Also, if you can get in amongst your plants, routinely turn the inner pot round 45° in the same direction every 2-3 days. This will make sure roots stay away from the tube and may also produce a more even growth pattern.
Note. IWS are working on a new root filter which will eradicates any root blockages. You will have to slowly increase your fill times to allow the water to soak through any roots which have worked their way round the filter.
Checking for Root Blockages
If you suspect your pots or pipe-work may be blocked you can confirm it by quickly flooding the pot, do this by pouring 5-8L of nutrient solution in from the top of the pot. If the solution drains away freely it’s ok, if it sits there and takes a long time to drain you most likely have a blockage. Note: this technique only works well with clay pebbles. If your pot is blocked you should remove the inner pot and check the inlet/outlet tube for roots or debris.
Minimising System Problems
Most system problems come about through not keeping a clean system. You must make sure your float switches in the brain pot do not become dirty or clogged with any growing media. Each time you refill the reservoir a quick rinse with fresh water over the switches will help prevent problems. If you do notice sediment or debris in the reservoir or brain pot, remove or clean it immediately.
Oxy-PotThe system has an inspection hole in the lid for you to quickly check your roots health and the EC / PH value of your nutrient solution.
Never let your EC run higher the 1.8 and never let your PH run above 7. The more nutrient solution under the net pot the better, as this gives a larger mass of nutrient solution for the root ball to feed from and the oxygen to mix with.
Never turn off the oxygen supply and lift the oxygen pump above the water level of the water. This will stop any water feeding back down the pipes and blowing the pump.
Frequently Asked Questions
How much space will my system take up?
Due to the way the system works, there is no exact answer to this question. When setting up, you can decide how much room to give each pot. We recommend giving each pot as much room as possible, this will mean your plants aren’t fighting for light and access will be much easier for maintenance. You can fit 4 pots within a square metre, though 2 – 3 per square metre is a much more sensible rule of thumb.
How often do I need to change the nutrient solution in my Flood & Drain system?
We recommend that you purge the nutrient tank once a week to remove waste and to give your plants fresh nutrient.
You should also pay attention to the water level in the tank throughout the week, making sure that there is always enough to feed your pots. The water-level will gradually drop, but particularly thirsty plants will accelerate this process.
Do IWS Systems come with any warranty?
In the unlikely event that your system develops a fault, we will repair or replace as necessary within the first 2 years of purchase. Please contact your retailer to arrange or call IWS systems directly for advice.
Warranty is for manufacturing and component faults only, it excludes accidental damage or damage caused by improper use. You should NEVER attempt to repair your system yourself as this will invalidate your warranty and you will endanger yourself.
Problem - My system fills but doesn’t drain?
Solution - This is usually a problem with the pump in the brain pot. If the pump is vibrating but not pumping it will be either air locked or blocked. Simply twist the pump so the inlet faces up, if air bubbles are released and the pump starts working the problem is fixed. If this happens regularly make sure the brain’s fill inlet is not pouring water onto or near the pump. If it is simply turn the elbow fitting so it is pouring onto the side of the brain pot and not splashing the surface of the water.
If the pump is vibrating in the brain pot, and does not release any air bubbles when turned it may be blocked. To service the pump you should turn the power off, remove the front of the case from the Maxijet 1000 and inspect the impeller and inlet. Remove any debris, replace the pump’s casing and check whether it is now working.
If the pump in the brain pot is not vibrating or pumping then check the bottom float switch. Check it can move freely, clean with water if not.
If after trying these solutions your system is still not working you will need to contact the retailer you bought the system from. Alternatively you can contact the returns/repairs department at IWS directly as you may have developed a faulty pump, timer unit or float switch.
Problem - My system won’t stop filling/my pots are over flowing!?
Solution - This is usually down to a siphoning effect that causes the pump in the reservoir to keep filling the brain pot at a reduced rate when the power switches off. Check that the anti-siphon valve in the reservoir is not underwater or blocked. The anti-siphon valve should be near the top of the reservoir and is coloured red and black. This allows air into the pipe when the pump turns off to stop the water from flowing. If you do not have an anti-siphon valve you will have a small hole drilled in the pipe work coming up from the pump at the top of the reservoir. Check that this is not blocked.
If your pump is not siphoning and carries on filling the brain pot at full power then it may be down to a faulty top float switch in the brain pot. Make sure that the float switch is clean and free from debris. If it is clean and not being forced open then you will need to contact the retailer you bought the system from. Or contact the returns/repairs department at IWS directly as you may have developed a faulty pump, timer unit or float switch.
Problem - Some of my pots are over-flooding!?
Solution - If you have an uneven floor and some or all of the pots are lower than the brain then you will get some over filling. You must ensure that all pots are at the same level as the brain pot, this is essential to how the systems works.
Problem - Why is the EC/CF is rising rapidly in the reservoir?
Solution - Nutrient strength normally rises slowly in the reservoir as plants generally use more water than nutrients. If your temperatures are high (above 29ºC) and relative humidity is constantly low (below 50%) the rise in nutrient strength will be accelerated. These environmental conditions can cause a quick rise in nutrient strength between irrigations as the nutrients will be accumulating in the pots. Add more water to the reservoir to dilute the nutrient strength and consider reducing the nutrient strength by 0.2-0.4 EC units (2-4CF).
This can also be a sign that your flood frequency is too low and the growing media is being allowed to dry too much between flood cycles. Consider increasing the flood frequency.
Problem - Why is the pH dropping rapidly in the reservoir?
Solution - pH drop can sometimes be a normal occurrence during the transitional phase from vegetative growth to flowering/fruiting. Adjusting back up with potassium hydroxide (pH up) or potassium silicate (Silicon) is recommended.
If the pH is dropping rapidly then it may be a sign of over-watering. If your flood frequency is too high and water is constantly saturating the growing media then oxygen levels become depleted. This drop in oxygen will cause the pH to fall. Another problem associated with over-watering is an increased susceptibility to root diseases. Check your growing media is not staying too wet between irrigations. If it is, consider reducing the flood frequency.
Problem - Why is the pH rising rapidly in the reservoir?
Solution - pH will normally rise slowly in the reservoir due to normal nutrient uptake by the plants. If you are finding the pH is climbing rapidly and you are adding lots of pH down it is normally due to your clay pebbles. Sometimes if you fail to wash the clay pebbles properly and do not pre-treat them with nutrient solution at the correct pH, a pH rise can happen in early growth. The pH will stabilise given time. If you are adding lots of pH down we recommend you use a mixture of nitric acid and phosphoric acid, this will help the balance of minerals in the nutrient solution.