The Flood and Drain (F&D) explained

[Shithappens]

The F&D Image

 

Sorry I can’t post flash images into here.....

 

This is just for some of the curious people out there that I figured would like an explanation of this type of system (Plus easiest of the systems to do the image for ).

 

The Flood and Drain (F&D) systems use a basic dunking effect at regular intervals to provide moisture to the root mass of the plants.

 

In order for this to be at the right time intervals and for the right amount of time flooding it is mainly an experimental affair so times provided will only be a guide within this article.

 

CONSTRUCTION HINTS

 

As you can see from the image the system contains 2 main tanks and a plant tray below the Net pots that hold the plants. The second tank will be explained in detail latter and is an optional part but highly recommended.

 

<The Tray Plumbing>

 

The tray shown below the net pots can be in several forms i.e. a bucket, golo tray etc. Generally it just needs to be water tight and held above the nutrient tank for the drain part of the F&D process.

 

 

For the pipe connections to the top tray I recommend the use of boating drain fittings (shown below) as these provide a solid screw on fitting that provides with the use of decent glue a permanent and secure fitting. But the rubber grommets are still an OK solution and also cheaper then the $8 au each for the boat fittings. But then for peace of mind the boat fittings are permanently water tight.

 

The bottom pipe can easily be done with 12mm garden hose connected straight to the pump but the top over flow should be at least twice the diameter to allow it to stop the rise of the water within the tray and the spillage that will follow if it does. Several Overflows back to the main tank can be used to ensure against this (I actually use 2 * 24mm drain offs and a third 24mm just in case one of the others blocks up with roots or clay balls)

 

The Overflow pipe to use should be flexible as this allows you to use not only the height of your outlets from the tray but also the highest point in the hose to set your flood level (see the setting your flood level to see why)

 

As you notice on the Flash diagram the pipes enter via a side point on the top tray this provides the to tray with a slight level of water which will provide a small amount for the roots. This stops them from drying out between the floods once they have grown into the tray. This water level is diluted and replaced each flood so don’t fear about any stagnant water fears.

 

The pump to be used should be able to fill your tray fast enough to provide a quick fill but not to fast to over flow your Plant tray and overflows. You do not wish to have them soak in the nutrients for longer then they need to wet all the roots either.

 

<Setting Your Pump Timer>

 

For this method I have found that the 15 minute division mechanical style of timer works well for this but your pump must be able to reach your height and the overflow must be sustainable for the full 15 minute intervals i.e. Not overflow your tray.

 

 

In order to set your timings between the floods I usually go once an hour as they are young and then as the plants age I watch them as they will start to show signs of getting to much water or to little(rarely) and you can adjust accordingly. This will be your time to get to know your plants and learn to know what they like. Remember the roots need to be always moist.

 

This I feel is the reason that these systems lost popularity as many people had troubles setting the flood cycle correctly.

 

<Flood Height>

 

I allow mine to flood within an inch of the base of the jiffy pots that I clone with. This is due to the fact that they absorb water like mad and seems to drown and weaken the plants at the base of the stem. But if you don’t use them you can increase this to a point that the medium you use needs it.

 

Any medium that soaks up water does not need to be flooded beyond one or two inches into the net pot as it will take up water to wet areas above your flood level. Once again plant free runs off your pumps with net pots of your chosen medium will help you set the level.

 

<Setting your flood height>

 

In order for this system to work well you need the correct flood height for your system and medium and to do this I use the runoff piping height to achieve the correct level. Thus the need for the outlet pumps to be flexible.

 

The pump timing gets your nutrient to the correct level and drains off once it can fall over the outlet opening but what if your outlet piping goes slightly higher then your outlet is connected to the tray????

 

What you get is a delay in which you can set the height of your flood by having your outlet piping going higher then your outlet connection this in fact raises the level that the water must reach to overflow back into your tank. Easy hey!!!

 

Using this method you can in fact have all your plumbing connected to the tray at the same height on the side of your tray and using something like cable ties you can set the exact height that you require. (cable ties don’t come undone as this is disastrous if your level setting does come undone)

 

MEDIUMS TO USE

 

I use a pure Clay ball medium in this method to allow a quick drainage but in saying that I find that as the plants get larger they need a higher rate of floods to keep them from wilting so a combination of perlite and clay balls of 1(perlite) to 2(Clay Balls) will combat the quick dry out of the medium. This again is a matter of experimentation but I find that the more floods is better then adding the perlite as the perlite can actually cause dramas in your plumbing if it escapes to much.

 

THE SECOND TANK AND FLOAT VALVE

 

Float valves are cheap as chips from any Tank or plumbing supply shop, I get mine for sub $20AU brass is better (and looks good ..) and they are easy to fit as the store usually provides the correct rubber washers.

 

The second tank I see as a must for hydroponics systems as it stops the problem of getting extra strong nutrients burning your plants. It does this by refilling the main nutrient tank constantly with the float opening the valve once it drops below a certain level.

 

When your plant decides to drink incredible amounts of water and not to take in many nutrients your nutrient tank can get very strong and this can cause problems for lazy sods like me.....

 

This system will replace the water to a set level whenever the flood occurs It does this as the flood pumps the amount of water needed to flood your tray from your nutrient tank once that level is reached if you are lacking water the ball of the float valve will fill your nutrient tank with pure water.

 

This also provides you with a way in which to evaporate the chorine in your water whilst sitting in the fill up tank. The only bad thing is it does allow your nutrient strength to drop when they drink considerably or be diluted but then we must do something every now and then no matter how lazy we are.

 

<Setting your float level>

 

If you get a float valve do not install it till you get your system up and running as you need the correct level of water used during a pump to mount it.

 

1// Mark your level of water when your pumping has been overflowing for a bit.

 

2// Now kill the pump and then remove what water you can from your tank to get your tank to the marked level.

 

3// Mount your pump so that the entrance of the valve into your tank is above the water and the valve will be just open when the float valve is floating on the water. Measure this by eye as we can adjust the float on most of these things.

 

4// Refill your main tank to the normal level and start your pumps and wait till they are using the overflows.

 

5// Now blow through the valve it should be closed and no air will get through if not read on.

 

If the valve isn’t closed bend the shaft to your float so that the float goes down into the water more and retest (If you go to far you will allow the water level to drop to far before it will fill up)

 

SUMMARY

 

This is one of the Older styles of hydroponics and the pros and cons of this system are a subject for great debate. But as this was a popular method when I had just started and it has been a major part in many of my grows, I figured it needed a bit of recognition for being a valid option.

 

I have since changed my system to more of a combination of many different systems mainly for the fun of it but still use a sort of flood to ensure my roots are wet at regular intervals.

[Shithappens]

Sorry i posted this initially incorrectly in the submission area but had no edit abilities in there so reposted here!!!

 

Either way i was straight when i did this draft so may be easier to read.

 

Any chance that the other post could get Deleted

[Stoney]

hey there shit

 

i can delete the origional if you wish but contact pure to see if he wants it left in the FAQ submissions untill he moves it into the proper FAQ section

 

get back to me

 

cheerz :Dj:

[Shithappens]

This is the updated and easier to read non stoned version!!!

 

The flash image i will also supply in a pre compilled version so yous can verify the no code status of the flash image and add within the page?

 

So yeh delete the other and keep this one!

 

Looking into doing another flash image for basic wick style followed by DWC system any other ones give a yell and ill do them when i get up to them.

[smoke p]

so u cant get better pics? ill just google it.

[Shithappens]

of what the float valves?

 

they are for tanks and are stocked in most hardware stores or plumbing outlets better to see the size of them first hand rather then accidently ordering one that is way 2 big online

 

The boat drain plugs are in most boating outlets and once again have many sizes so ring a few and ask them they all should know about them