First DWC Grow.. would love some feedback

Hey there-

Newbie/oldie here.
I have grown outdoors for about 10 years on and off and a few years indoor with soil in college so I decided to give a DWC system a go.
I built my own set up using a 27 gallon well(18 gallon nute solution for 4 sites.
The system has two air pumps running:
4, 4x2” airs stones under each plant site as well as a fixed 12inch bubbler stone in the middle to offset any current created by the airstones.
I just put them to flower (12/12) on 7/16.
They were vegging for two weeks with a 24 on the first week, then 18/6 Second week, then the third week
Slowly dialed back light an hour a day increased light intensity then went to 12/12.

My First week I did what seems like a lot if first timers did and overnuted the sh*t out of the transplants so it took a good week to flush out and get them healthy. So they really only veg’d for 2 weeks in my ignorant opinion. Ha
Current Environment:
Air temp ranges from 72 to 81degrees Fahrenheit
Water temp ranges from 70 to 73.4 degrees Fahrenheit
Humidity ranges between 49% to 64%
Root medium: clay pebbles in 4 inch pots

The last solution change was the beginning of the third week and started them at 500ppm’s
The Ph ranges from 5.8-6.1
I have been upping the nutes by about 25 ppms a day and have been at 600 for last day or two.
I use general hydroponics (green/orange/brown) nutrients, as well as
Hydroguard currently.

Sorry I am allover the place trying to give as many details as i can.

My concern and reason for my post is that the color of my leaves are a bit lighter than I expected and compared to the mothers and I was not sure if that is cause by a silica deficiency or is it normal or is it something else or am i being over critical. Do i need foliage spray?
The reason i suspect it could be a silica issue is because the mothers have had a lot of silica in their soil(use DE To deter pests and as a secondary effect To condition the soil a bit).
I just ordered botanicare silica blast And plan to add that this weekend just in case.

Any advice would be greatly appreciated…


I’m far from an experienced dwc grower, in fact only thing I’ve grown hydroponically is lettuce. But I do have some feedback that I think would be helpful.

Download yourself a vpd chart and try to keep in recommended range for stage of growth you’re in. Even if it’s not perfect, working towards ideal is usually plenty good enough.

This seems a little high. You will probably be fine with the hydroguard and buttload of air though.

Nothing wrong with playing the swing, but I fear 6.1 is a little high and may be cause of what you’re seeing. You can see what the others suggest, but I tried to keep mine between 5.7 and 5.9, seemed to work pretty well.

I try not to spray my plants with anything. If I need to spray for bugs, always do it right at lights off so it has time to dry before pounding wet leaves with light. It will burn the leaves.

I use this, it will play with your ph. Something to be ready for if you’re not experienced with it.

I haven’t, but a lot of the successful growers I see ditch the grow bottle and use Lucas formula. May be worth looking into. Also noticed no calmag, may want to at least have a bottle around.

Thanks for the info! Super helpful.
In regards to the humidity/air/water temp
I forgot to add that i will be adding a CO2 system this weekend which will help bump up my humidity and lower the ambient temps of both air and water a bit. I am pumping a ton of air in there as i knew that and hydro guard would help alleviate some concerns with rising water temps.
I will look into the ph and see if 6.1 is on the high side.
I have cal mag as well. However, I did not add to nutes and have only used it for prepping coco coir for an outdoor continuous drip site I have. I did not know I should consider adding that to nute solution… I will look into that.

I also have ph down in anticipation of the silica and it’s effect so i will do my best to manage that.

I just pulled the chart you recommended thanks

Also, thanks for the foliage spray feedback. I concur and prefer not to spray the plants if i can help it.

Thanks again for reply and advice!

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Quick update: just gave plants a final trim, set up screen, and starting the 4th week of flowering this Monday. So far all seems dialed in. Update in a few weeks fingers crossed But things seem to be going well…

Tanks and regulator? Closed loop system with full environmental controls? At least 1,500 µmol/j/m2 lighting? If not then this is a waste of time. In addition; unless you have full climate control your temps will go way up.

Air pumps outside of closed grow space: that way there’s plenty of O. Air pumps will add heat to solution.

If you are still top feeding it’s time to discontinue. Rez level should be 1 1/2 to 2" below net pot and if it’s not you run the risk of stem rot and of course damping off.

If you have gucci lights you will need to run supplemental cal mag.

5.3 to 5.8 is hydro range.

750 to 800 ppm should be your target in veg and they are big enough now. Color looks good other than residual nute burn.

Diotomaceous Earth is not a really great source of silica. Silica will harden stems but will also promote a healthy ‘skin’ surface to protect against infection. Needs to be added before anything else FYI, then Cal Mag, then everything else.

18 gallons for 4 plants is not a lot. In mid flower they can drink a gallon per plant per day. Without a check-rez you will be filling tote daily. Strongly recommend investing in a chiller and a decent standing rez to help maintain levels.

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Thanks for the feedback!
Basically every issue i have found with the system i designed your pointed out haha.
Main issue is well size they are sucking up water so i need to add about 4 To 5 gallons every week.

The air temp control I am doing well with actually well i think. I have a strong a/c running at 73 degrees all day and night with keeps the temperatures at bay my overall temps are floating between: 70 and79 degrees with 60 to 70% humidity.

The water temps temps have been a bit lower than before i think because the plants canopy is covering well cover completely so it has Stayed around 68- 71 degrees.

I just picked up a 50lb CO2 tank from my buddy Today and will be setting that up later.
Tonight. I will run a Closed loop system with t bar connector. Was going to run a single line but will loop it thanks for the advice. I will post a pic once i am set up.

I am going to move the pumps out of shower(yes that is a 32” x 32” prebuilt shower stall when I first saw it thought perfect little grow closet) to help disperse any heat they produce.

Nutewise… I am running 1200ppm using a general HP Products following Lucas theory to a degree, also supplementing with Botanicare Hydroguard and silica blast.
Lastly using gerneral hydro flora bloom product.they seem to love it. No signs of stress and they seem to be praying as soon as the lights go on.

I am not using the cal mag yet but will look into that i keep forgetting to add it to mix.

Growth has been doubling every week. My concern is my light height… I am going to put two rings in the ceiling and hang lights from there it should help A little

Ph is Steady at 5.8-5.9 For most part. It will drop once in a While to 5.6-5.7 but that is usually the time I need to add water/nute solution to well due the plants drawing about
a 1-1.5 gallons a day. The nute solution i add is about 6.1 so it ends up bringing the ph back down to 5.8-5.9 and then I just rinse and repeat.

The light is about 14 to 16 inches from canopy top and according to manufacturer that puts me at a par value of about 2000 which I really don’t believe is accurate. I will bump them to about 12 inches If that makes a difference it will bring the par up to 2252 according to manufacturer. We will see i guess. Will post some more pics in a few weeks .
Thank you very much for the feedback it is always really helpful and I learn something new every time I post. :+1:t3:

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