DWC System Advice

About DWC Systems

 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.

Our 3d movie section goes into detail on system assembly and how each system works.

Here we will try to give you advice on all aspects of using the system, giving you a better chance of success.

Which growing media?

Planning your grow schedule

In order to get the best possible result from your DWC system you must ensure you get the flood cycle right. On a DWC you need to think about 2 factors;

Frequency – I.E. how often you flood/drain the pots. On a DWC system we recommend draining back to the main tank for 30 minutes every 8 hours. After the 30 minutes elapses, the nutrient can be pumped back to the pots, having been remixed in the nutrient tank.

Flood height – This is how high the water goes in each pot. As the system is controlled by float switches, this level is already set.

Both these factors will have an effect on your success.

We recommend changing your nutrient solution once a week. As time passes, the EC in the tank will also rise as the salt level increases due to waste. Drain the tank completely and replace with fresh nutrient to keep your plants healthy.
 

Environmental considerations

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 more often

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. 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.
 

Maintenance

Avoiding root blockages
Because a 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 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.

Checking for Root Blockages
If you suspect your pots or pipe-work may be blocked you can confirm it by quickly flooding 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. If your pot is blocked you should remove the net 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.