Does DWC require way more nutrients than soil or I'm making a mistake?

Hey guys, hope you're healthy and well. I really want to start growing in DWC because I'm amazed by most of the results online. In soil, I'm used to growing in 15-19Lt. pots and I water 1.5Ltr water with nutes every 2 days. So that would be 4.5Ltr water with nutes per week. If I start using DWC, if the bucket is 19ltr that requires water change once a week(some say once every two weeks), then I would spend 19ltrs of water WITH NUTES per week instead of 4.5ltrs like in soil. Are my calculations correct or no? Thank you and God Bless.

With DWC, the concentration needed isn't as much, but your still wasting some unused nutes during res changes. Some can get away with little to no water changes, but I like to do it weekly/often just to be safe. I buy dry fertilizers anyway (jacks hydro) so I feel like i'm saving money compared to buying expensive watered down versions anyway. You definitely don't wanna start throwing any kind of organic soil only type fertilizers/addies in there, and make sure whatever you use is good for hydro. Keep it sterile.

You will be able to dial in exactly what the plants need, unlike soil with its many variables. With DWC, less is more, and the plants will take what they need as long as you keep everything in range. If you haven't already, get a TDS/PPM meter, so you can measure everything. Start low at around 300ppm with small plants, then work your way up to 500 or so for the remainder of veg.

You'll be able to tell how much they are feeding because as the water level go's down, the PPM nutrient level will either decrease, stay about the same, or be higher.
- if lower, then slightly raise the strength.
- if it's about the same as you started with, then you are pretty much on the money, and using the perfect amount. You could just top off and PH for a bit longer if you wanted.
- if higher, then you should back off. No point in wasting more than what the plants need, and it affects the ph range making it swing faster, or cause other issues.


In flower I've never seen plants take much more than 750-1000 PPM max. Some people go higher but I don't really understand why. If you just give what they need you don't even need to flush towards the end, just slowly decrease the last week or so, and end up with a nice smooth product. If you pump them with like 1200+ PPM up until week 5-6+ then ya you gotta flush them out good for 2 weeks. Still probably taste like fertilizer after you flush anyway.. I prefer to let mine get real hungry and slowly yellow/color out at the end, but to each his own

Also, its always smooth sailing through veg.. its around flower when you'll really need to keep up on everything. The levels will really start swinging all over the place, and the plant will actually start expelling waste back down through the roots into the solution. I would get the biggest bucket or bin that you possibly can. Then you could veg off a single fill for months if you really wanted, and have a nice stable res throughout flower with minimal res changes. With a 5 gallon bucket, you might as well expect to change it every day or so at some point. I would just have a few days worth of fresh buckets ready at all times if so.

Drop That Sound said:

Also, its always smooth sailing through veg.. its around flower when you'll really need to keep up on everything. The levels will really start swinging all over the place, and the plant will actually start expelling waste back down through the roots into the solution. I would get the biggest bucket or bin that you possibly can. Then you could veg off a single fill for months if you really wanted, and have a nice stable res throughout flower with minimal res changes. With a 5 gallon bucket, you might as well expect to change it every day or so at some point. I would just have a few days worth of fresh buckets ready at all times if so.

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Thanks a bunch for all this information. You're the man. I will get the 8.5gal bucket from 420 hydroponics then. Just one question, how come you say to flush for 2 weeks when most say 2-3 days is fine for DWC?

Welcome! The more solution you have in the container the better, and more stable it will be. You want the level to stay 1/2" to 1" under the net pot, so that right there uses up almost a 1/4 to 1/3 of the over all capacity in most buckets/containers. In a 5 gallon bucket (depending on how big your pots are) that leaves you barely 3 to 3-1/2 gallons total, so that right there throws off your original math lol. You only have around 2/3 of the bucket full usually.

And ya, there really actually isn't a need to flush DWC at all if you feed lightly like I do.

So with the taller 8+ gallon buckets, then you will possibly have a true 5 gallons (same as 19l right?) of solution in the container. That extra 2 gallons will make a huge difference on maintaining it.

If growing multiple plants, you would probably be better to use one big light proof plastic storage bin, with multiple net pots installed in the lid. Or convert your buckets to an RDWC system eventually, so you only have one res to maintain instead of many buckets that have different variables.

Drop That Sound said:

So with the taller 8+ gallon buckets, then you will possibly have a true 5 gallons (same as 19l right?) of solution in the container. That extra 2 gallons will make a huge difference on maintaining it.

If growing multiple plants, you would probably be better to use one big light proof plastic storage bin, with multiple net pots installed in the lid. Or convert your buckets to an RDWC system eventually, so you only have one res to maintain instead of many buckets that have different variables.

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Thanks my friend. No I will start with one plant for sure and I will try my best to not f.ck it up. I'm still in soil and I will start my first DWC in November. I've done as much research as I can. I will send you pictures if you want. Any high yielders you recommend? I'm thinking Gorilla Zkittles from Barney's Farm. It says 750gr per sq.meter but I'm really aiming for 300-350gr. I will be using an 2.3ftx2.3ftx4ft mars hydro tent, as well as MarsHydro TS1000 which is 150true watts. I think it's enough for one plant. As for nutes, I hear when you use GHE in DWC the roots turn brown. Maybe because despite its the most popular brand, it is not meant for cannabis. I will try Advanced Nutrients or Canna. R.I.P. my wallet lol

Eugenios said:

when you use GHE in DWC the roots turn brown.

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the micro will stain the roots. root rot will turn the roots brown and slimy.

rkymtnman said:

the micro will stain the roots. root rot will turn the roots brown and slimy.

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So what nutes are you using?

I've done entire DWC grows with nothing but GH flora nova bloom. It does stain the roots slightly.. but talk about a simple grow!

Eugenios said:

So what nutes are you using?

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i've used a lot: GH flora, GH maxi, GH floranova, CES 3 part, Dyna Gro, Ionic and my next run will be Jack's