Ready for giant yields in system that’s easy to manage with a flexible layout? Invest in the tried, tested, proven 16mm IWS Flood & Drain System.
How's it work? It’s all about getting oxygen to the roots.
When feeding, plant pots are flooded with feed. When feeding ends, pots are quickly drained of feed. This locks oxygen in the rootzone, to drive nutrient uptake, fuel growth & prevent nasty root diseases.
It's simple, but it works.
- Flood & drain growing system
- 13mm inner diameter pipes (16mm outer diameter)
- Handy fixed timer (1 minute segments)
- Flexible, modular layout – position pots how you want
- Easy to manage – pots are filled from a 1 tank
- Quiet – the pumps hardly ever on!
- Saves headroom - pots sit on the floor
- Low waste! Drained feed is stored for recirculation
- Extreme oxygen – better roots, growth, nutrient uptake
- Simple to set up and program
Waste is low - drained feed is stored between floods. It'll run quietly too, the pump's hardly ever on!
It’s easy to fine tune your flood times– you get a fixed timer (1 minute segments).
Your layout’s flexible…expand it & position pots however you want – all pots are connected to a central feed tank individually or in groups. Pots sit on the floor too, height's hardly an issue.
See it in action
1. Choosing your media
Use clay pebbles – they hold lots of air, but hardly any nutrients. They’re perfect for flood and drain.
To flood less often, mix 20 – 40% of coco with 60 – 80% of clay pebbles. The mix will hold more water, so you can flood less often. You can mix this yourself, or buy it pre-mixed.
2. Keeping a sterile system
Keep your system sterile with Silver Bullet Roots. It kills 99.99% of root diseases and stays active in tanks for 5 weeks!
If you already use Oxy-Plus 11.9%, switch to Silver Bullet and you’ll save 55%.
- The Science
What’s flood and drain?
It’s a tried and tested way of getting lots of oxygen to your roots!
You fill your pots with a growing media (like clay pebbles) that holds a lot of air, but not much water.
Periodically, you flood pots with a nutrient solution, then quickly drain it away.
With each flood:
• Stale air is pushed away from roots
• Fresh, oxygen rich air is drawn into the root zone
• Your media gets a hit of nutrient solution, which it slowly releases to roots
Why does flood and drain work?
It’s all about supplying your roots with lots of oxygen.
Oxygen in the root zone:
• Stimulates root growth
• Increases nutrient uptake
• Helps prevent root diseases, such as Pythium
• Increase cell growth/activity
• Stop water from stagnating
Without enough oxygen
• You’ll likely experience:
• Mineral deficiencies
• Poor growth
• A decrease in water and nutrient absorption
• Underdeveloped roots
With an IWS Flood System, your plants will always get the oxygen they need.
- How to Use
Assembling your system
It’s easy to assemble your IWS Flood System. Watch this video to see how.
Feed Time Guide for 60/40
- Start: 2 x 15 minutes feeds per day
- Veg: 3 x 15 minute feeds per day
- Flowering: 4 - 5 x 15 minute feeds per day
Feed Time Guide for pebbles:
- Start: 2 x 15 minutes feeds per day
- Veg: 3 - 4 x 15 minute feeds per day
- Flowering: 4 - 6 x 15 minute feeds per day
Choose your nutrients
For best result, use it with SHOGUN Hydro Nutrients – the best base feed for hydro systems.
Choose your growing media
Use clay pebbles as your growing media – they hold lots of air, but hardly any nutrients. They’re perfect for flood and drain.
If you want to flood less often, mix 20 – 40% of coco with 60 – 80% of clay pebbles. The mix will hold more water, so you can flood less often. You can mix this yourself, or buy it pre-mixed.
Prevent root blockages
Place RhizoPots on the inside each pot to prevent root blockages. They naturally air prune roots, so they won't grow into your feed pipe and cause blockages.
- Q & A
Questions and Answers (12)Is it OK to use the 6 pot IWS system with a 1m x 1m tent?The smallest tent we would recommend ofr the 6 pot IWS Flood System is the XL Budbox, which measures 1.2 x 1.2m. You will need to have ther reservoir outside the tent for best results.
Written by Keith | 4 Jul 2014Hi, is there a grow tent which can accommodate an IWS 48 pot system?We would recommend using 2 x Titan 2 Budbox tents for the 48 pot IWS flood system, 24 plants in each tent.
Written by Duncan | 11 Jul 2013What size iws systems would I fit in a, 1.2 x 1.2 tent, and a 1.2 x 2.4 tent? I would like to purchase one for each but need to be sure of what I can fit in each of them.You can get the 6 pot IWS Flood system in an XL Budbox (1.2 x 1.2), & you will get a 12 pot into an XXL Budbox (2.4 x 1.2). You will need to have the reservoir outside the tent.
Written by JC | 11 Feb 2013Hi guys I have just put my 48 pot system together which I got from you guys and I wanted to know about draining the system. Should I be draining the system back completely after each feed or just when changing the nutrients?We would recommend completely draining the system back after each feed.
Written by SA | 21 Oct 2012What size tent might you use for the 6 pot system?.The 6 pot IWS Flood System will fit in the XL Budbox tent, which is 1.2m x 1.2m. It is best to locate the reservoir outside the tent. For larger plants, you may want to consider a 1.2m x 2.4m XXL tent.
Written by LC | 2 Sep 2012What size system would you recommend for a 2.4 x 2.4 x 2 tent?? ThanksYou would be able to get a 24 pot IWS system in this tent, It would be preferable to locate the nutrient reservoir outside the tent .
Written by Ian | 9 Aug 2012Hi i have brought 2 iws systems from Growell. Could you give me some advice on flood cycles in veg and flower stages, do the cuttings have to be well established before transplanting them into the system?We would advise that the roots of the plants should be well established before putting them in the system. For young plants in the system, we would advise that you set the system to run for 15 minutes every 3 hours, & once during the lights off period, for more mature plants, we would advise running the system in for 15 minutes every 2 hours, & twice during the lights off period.
Written by nigel | 7 Aug 2012Hi, I will shortly be placing an order for 12 pot IWs flood system, do these systems require reservoir heaters and if so which wattage, also do they require any air infusion pumps? ThanksWe would recommend using the 300W Heavy Duty Nutrient Heater with the 12 pot IWS System. If you wanted to use airstones in the reservoir, we would recommend using the NFT Aeration kit 3, which includes the four outlet budget air pump, with 4 airstones & airline too connect them.
Written by TC | 28 Dec 2011hi do i need to flood it every 2/3 hours even when lights are off? I was told plants don't feed at night.You would only need to run flood cycles with the light on in this system, as the night period will give the roots a chance to rest, this is the case for all flood & drain systems, & dripper systems
Written by gary | 9 Nov 2011Hi, other than changing the solution and checking ph/cf levels, what else do you need to do to maintain the IWS system? Would I have to clean all the individual buckets every week like with oxy pots?We would recommend thoroughly cleaning the entire system between crops, & changing your nutrient solution every week.
Written by JB | 19 Aug 2011what the size of the water tank on the 12 pot system acrossThe 12 pot IWS Flood system uses a 190 litre reservoir, which is 69cm across at the top.
Written by babyj | 7 Jul 2011Hi. Would you be able to provide me with the diameter measurement of an iws flood & drain outer pot. Many Thanks.The IWS Flood system pots are 29cm across.
Written by AW | 21 Jun 2011