TealAtlas: RDWC Hydro, Gelato/Blueberry, 2021, First Hydro Grow

[tealatlas]

TealAtlas' First Hydro (RDWC) Grow - Gelato & Blueberry!

Strains:
Feminized Gelato (Hybrid 55% Sativa/45% Indica) @ Crop King Seeds
Feminized Blueberry (Indica) @ Forgot Breeder

Environment Specs:
Indoor Fabricated Grow Tent, 9.5' x 6' x 5'11"
Starting Temp: 73°F
Starting RH: 50%

Hydro Specs:
Hydroponic RDWC, Current Culture CCH2O Under CurrentUC4XL13 (4 13gal modules)
100gal top off res (located on the outside of the grow area)

Cultured Solutions Nutes

Light Specs:
LED, Phlizon Cree COB Series 2000W (HID Equiv ~600w)
LED, Phlizon Cree COB Series 3000W (HID Equiv ~750w)

---

Now that that's out of the way... I started germing seeds on 3/14/2021. So excited (and terrified) to get started with hydro. I've researched the hell out of pretty much everything I can at this point, so it's all up to trial and error going forward!

 

[tealatlas]

3/16/2021 - We've got tap roots on 3/4 seeds... 2 Gelato and 1 Blueberry.

I have never transplanted into rockwool before, so I just buried the seedling and piped a small amount of spring water (pH 7) onto the rockwool. Current Culture net pots come with a raised planting deck, so I placed the rockwool on the planting deck with RO water (pH 7) and surrounded it with hydroton. As of now there are no nutrients or cal/mag in the system. I have pH'd the top off slightly lower as I'll be targeting ~pH 6.5 in week 1.

Meanwhile I'm still waiting for Blueberry #2 to pop!

 

[tealatlas]

3/17/2021 - Tap root on Blueberry #2. Moved to rockwool like the others and placed in grow space.

I bumped the temp and humidity up in the tent during this stage temporarily from 73°F/50%rH to 75°F/60%rH.

 

[tealatlas]

No real update, getting close to starting veg... but here are some nice photos of the girls:

 

[tealatlas]

Once again no real update, but I always enjoy watching seedlings sprout. Here are the same photos about 12 hours later, after the girls had their dark period for the night.

 

[tealatlas]

Seedling tracker:

 

[tealatlas]

Veg is coming quickly... will probably start week 1 nutes at half strength on Monday 3/29 and titrate my way up to 75-90% of what's recommended.

 

[tealatlas]

One of the four stunted herself for a few days, but seems to be back on track.

 

[tealatlas]

We're getting ready to explode into veg!

 

[Rexer]

Hey @tealatlas, mind if I join along?
I'm no pro but have a small amount of experience.
That's a beautiful setup you got there and good job with the seedlings

If I can make a small suggestion or two? Target you ph to 5.8....then let it naturally drift to 6.3 and reset to 5.8
This is the ideal range for Hydroponics with cannabis.

Do you have a TDS/EC type pen?
This chart will help a lot when used with it

Most rockwool needs to be pre-ph'd before adding seedlings as it can be rather akalaline.

 

[tealatlas]

Hey @tealatlas, mind if I join along?
I'm no pro but have a small amount of experience.
That's a beautiful setup you got there and good job with the seedlings

Not at all! I'm 2000% percent open to input. Had a ton of great input from @Backlipslide and @Silverfox125 last time around

If I can make a small suggestion or two? Target you ph to 5.8....then let it naturally drift to 6.3 and reset to 5.8
This is the ideal range for Hydroponics with cannabis.

Do you have a TDS/EC type pen?
This chart will help a lot when used with it

Most rockwool needs to be pre-ph'd before adding seedlings as it can be rather akalaline.

Great idea on the 5.8 target... I noticed the trend of rising pH but I didn't know that it was a normal occurrence. I do have a pH meter and a TDS pen, and this chart is probably more helpful than most of what I've found on the internet. Thank you!

Also -- I knew about pre-pHing the rockwool. Totally and 100% slipped my mind. I tried to compensate in the beginning with soaking the rockwool with more neutral water after the seeds were planted, but I think it was a lost cause by then anyway. Thankfully we seem to be doing pretty well, roots have made it out of the bottom of the net pot... and growth is getting pretty quick.

 

[tealatlas]

Started week 2 nutes today. Pre-change, the system was at pH 6.5. I had pH'd the top off res and new nutrient solution at 5.8 and did maybe an 85% change (I guess because I was concerned about the hard pH fluctuation?) After the change, the system pH was at 5.9 (which is pretty close to perfect AFAIC) and the PPM was in the 130 range (down from 200 in the res.) Cultured Solutions recommends that the PPM be at 200, and I don't have the "add-back kit" to add more nutes in-between changes. Is it okay to run nutes low like this early on? Can I just make small nutrient changes in the epicenter and periodically check EC? I feel like these are dumb questions tbh

 

[Rexer]

Started week 2 nutes today. Pre-change, the system was at pH 6.5. I had pH'd the top off res and new nutrient solution at 5.8 and did maybe an 85% change (I guess because I was concerned about the hard pH fluctuation?) After the change, the system pH was at 5.9 (which is pretty close to perfect AFAIC) and the PPM was in the 130 range (down from 200 in the res.) Cultured Solutions recommends that the PPM be at 200, and I don't have the "add-back kit" to add more nutes in-between changes. Is it okay to run nutes low like this early on? Can I just make small nutrient changes in the epicenter and periodically check EC? I feel like these are dumb questions tbh

Don't by any ad back Stuff, that's just a gimmick in my books.

you can top up with whichever you'd like:

Reverse osmosis water ph'd to 5.8

a small batch of nutes (mixed up to a target PPM of your reservoir desired ppm). Ph to 5.8

You can also mix up a batch of nutes at a stronger PPM to top up, to reset your res to before feeding, but watch you don't accidentally raise your reservoir PPM too high. If you do, take some out and dilute with water pH'd to 5.8

 

[Rexer]

I'm going to tag @KCCO 77 in to see if he's able to follow along as well. He's a much more experienced grower and well, he's also a better writer! He's also doing a RDWC so you may want to read over his journals.

Hopefully till more members join over between us any questions you have won't slip through.

Oh- and take his advice over mine if I made a mistake in your reservoir top up question!

Hope you don't mind the tag in KC, I know you're helping a lot of growers at the moment

 

[KCCO 77]

Hey there I hope all is good.
Im at work now on lunch so let me get home and read up on your grow as I don’t want to miss anything like this.

Great idea on the 5.8 target... I noticed the trend of rising pH but I didn't know that it was a normal occurrence. I

Ph will almost always raise when plants r feeding happily at the numbers your running. The ph rising is normal and if your ppm/ec is dropping then your in the sweet zone and with some minor tweaking they should be on point.
Im pulling up a seat and will be back around this evening when I get caught up.
Your in good shape and @Rexer will keep you on point.

play safe and enjoy

 

[tealatlas]

Thanks so much for the help @Rexer and @KCCO 77! This is my first run in hydro and my second grow in general, so I am down for input from anyone and everyone on anything and everything. Hopefully the answers to my dumb questions will be helpful for someone in the future.

Overall things are going well. My environment is stable (for the most part, temps are running a little high right now but airflow is good) and the plants seem to be happy. pH is in a good place for them, even if PPM is currently running low. (Thanks for the advice on that by the way!) Node spacing is super tight right now, and I'm just starting to see the leaf tips of future node 5, so I need to get my ass in gear and build a SCROG this week.

I'm pretty limited height-wise, and these Phlizon CREE COBs are no joke. I'm not sure if I will top two or three times. Gelato is reasonably short for its Sativa genetics, I'm just not sure what will maximize yield for my short grow space while giving me ~10" of walking area

But... current (tentative) priorities: fixing the nutrients, building a SCROG, topping the girls, and then increasing airflow even more.

 

[KCCO 77]

Hey brother I hope all is well.
Sweet setup from the space to the system.
Top to bottom it’s all just very clean.
Running and keeping a clean grow will avoid a ton of problems I hope you never encounter.

Your in good shape over here.

I do have ? because I’ve never seen a true cc system in action.

I know you have a 100L master res outside of the grow.
Is it full right now?? Seem like a large amount of RO/nutrient to run that whole system for seedlings.

Hypothetically: Could you run without it when the plants r babies it would be cheaper and less water. They won’t start drinking to much until you get foliage growing.
Do you know how much water is in the 4 buckets and the res in the grow room?

My 10 plants when vegging on my flood and drain table only drink about 5 L a week at 12 inches tall.

How often will you res change?

Play safe and enjoy

 

[tealatlas]

Hey brother I hope all is well.
Sweet setup from the space to the system.
Top to bottom it’s all just very clean.
Running and keeping a clean grow will avoid a ton of problems I hope you never encounter.

Your in good shape over here.

Thanks for the kind words! I'm an automation engineer IRL and my goal with all of this has been to spend as much time training the plants as possible, as opposed to micromanaging pH and nutrients... mitigating potential issues in advance, etc.

I do have ? because I’ve never seen a true cc system in action.

I know you have a 100L master res outside of the grow.
Is it full right now?? Seem like a large amount of RO/nutrient to run that whole system for seedlings.

I have a 100gal res outside of the grow area with a BlueLab pH controller connected to it. I have RO always coming into the res via a top off valve that I can set to whatever level I want. I also have a manual shutoff if I want to stop it at a certain place below the float as well as a valve override.

It does happen to be "full" right now (~70 gal, total system volume ~60gal), with RO pH'd to 6.5. It's not actually topping off the system right now though because my system's water level is pretty much static given the stage the plants are currently in.

Hypothetically: Could you run without it when the plants r babies it would be cheaper and less water. They won’t start drinking to much until you get foliage growing.
Do you know how much water is in the 4 buckets and the res in the grow room?

I am pretty much running without it topping off right now, but yes, I could run without it at this stage in the game. Each "module" is a 13gal bucket with an approximate volume of 11gal + 10% for joints & manifolds = a total system volume of 60.5gal.

My 10 plants when vegging on my flood and drain table only drink about 5 L a week at 12 inches tall.

How often will you res change?

For now, I'm changing nutrients once a week based on the Cultured Solutions feeding schedule. Since this is my first time going hydro, I'm just going off of their schedule as a baseline and I'll change it as needed.

 

[KCCO 77]

You got this and take it all in now.
At times it will seem like a lot but it will be second nature sooner then later. Between your setup and eye for detail as well as 420 you’ll be fine.
As you mentioned people helped you before and there’s a lot of help out here.

Play safe and enjoy

 

[Michael Hunt]

Hey @tealatlas Mind if i pull up a chair for this one? I'm a sucker for DWC and RDWC grows and you have one clean set up in there. We actually eyeballed this kit before building our own RDWC system. So clean and simple.

I hear from a few others that bluelab controller is the business. Any thoughts on it you'd care to share?

You have one mighty fine set up in there, i cant wait to see what you can grow out of it