DWC and RDWC multi-bucket help.

I have seen quite a few DWC setups that keeps everything on the same level height wise and I can't seem to grasp a full understanding of the system. When you have a DWC bucket system that is linked, each bucket has it's own "bath" correct? So why the resevoir? I've seen that it helps with res changes but how do you get the nutrient water out of the buckets?

To flood the buckets with the bath, do you simply open a valve and leave it open until the levels equal out between all the buckets and res? How does this not pull back on efficiency numbers? Your not using a good portion of the nutrient bath the way I'm seeing it. To me it seems as though a lifted table the height of your water level in the res for the buckets to sit on would allow a quicker/more efficient return for the nutrients to the res...but eats a good bit of light room.

RDWC now, is it simply a DWC that constantly circulates or is there something else to it?

I may be completely confused, but it's my next type build...

I use a straight up dwc with a 50 gal rez and 4 netpots in the same rez, works pretty effeciently but the problem I have ran into is noe that I'm 4 weeks into flowering, to change the water and clean out the rez I have to lift the top, which is very heavy and delicate, I don't want to mess with that anymore. So my next system I will have an external rez at the same level as four 5 gal buckets, the main rez will pump water into and out of each bucket. This way I can just use my main rez which is out of my grow space to adjust nutes and what not with out having to mess with the buckets that are holding my beauties. Maybe this helps!!??

I understand that you can pump in/out of the buckets but what happens when the buckets go semi-dry and your pump is running to get the last of it? Does that not damage the pump at all?

What about the remaining bits of the nutrient bath in the buckets and lines? Does that not affect anything?

no air through the pump won't damage it... use a clean water flush when changing nutrients... i've spent alot of wasted time trying t oget levels exact and learned over the years it doesn't matter... as long as the salt content in the water doesn't exceed the salt content in your plants and you have a constant food source they will thrive.

ok from what i know if you have a multi bucket dwc system the reservoir it to maintain water levels in all buckets so if one plant is drinking a lil more then the rest that one plant will not run dry just like if you were drinking out of a cup and it had auto refill on it. just help keep you from mixing nutrients every couple days hungry plants use a lot of water this way its there when they need it . flowering plants can use water and nutrients fast they can empty a 30 gallon res in a week or so the system i am building will have a 30 gallon res and a 55 gallon backup res that will sit higher than the control res this way my mi will last as long as i need it to when its time to flush and change i just use the return pump to pump the old mix into the toilet then i fill the 55gl res up with clean water and some h2o2 and run it through the system for a while the pump that into the toilet then fill it up mix nutrients and start her up again

here is a couple links that may help you understand http://youtu.be/homrqMp10_w

http://youtu.be/vq0ppgAvm8M

thanks man, i just don't understand how the reservoir levels the buckets out because if you have a res with a water level higher than what you want the buckets to be then you are going to flood out of the buckets...or at least I see it that way. Is there like an electric valve on that upper reservoirs line that only allows so much water through or what?

edit: i see the float like your gas tank uses on the second vid, but what about the first?

Gravity keeps the water level the same in all the containers. You fill the reservoir to the same level as you want in the buckets. You pump out of the reservoir, water level wnats to rise in the buckets but gravity pulls it back to the reservoir. Your return lines from the buckets to the reservoir need to be larger than the feeder lines. You might have to dial down your water pump if you have a large one to get everything balanced at first. I run a 300+ gph pump and run it about 75% open.

You can put a float vaulve in your reservoir that is connected to another bucket that sits on top of the reservoir. As your plants drink, the bucket resupplies the reservoir with water keeping it at the same level. Fill the top off bucket every 3-4 days. You can kind of get an idea from these: