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Second Grow - Deep Water Culture, 400w, Black Jack and Friends


New Member
Hi all,

Starting my second grow tonight. My first grow was 3 fem Purple Wreck. I used CFLs, Deep Water Culture in a 2x3 space. I got a pretty crappy yield of 49.5 grams plus 2 gallon sized ziplocks bags of trim leaves for cannabutter. The bud smokes very smoothly and I made a great batch of salty oatmeal cookies that are a hit (my other hobby is baking).

My goal this time is to increase the yield. My impression was I needed to change a couple things to bring the yield up - more light and more room. I switched to a 3x4 closet and bought a 400w lighting system. The ballast is a nextgen switchable so I will be using it for veg with a metal halide bulb then HPS for flowering.

This time I am starting with 5 fem black jack seeds. But I have some kali mist, NYPD, and Laughing Budda on order from Attitude. Plus Attitude is sending a ton of free seeds. As soon as those arrive I will be added a second bubble tank and 5 more plants to this grow. But for now I am starting with the 5 black jack.

All the equipment has been washed and is ready to go. The seeds are soaking and tomorrow will be day 1.



New Member
Planted this morning.

Here is the tank with the 5 fem black jacks. You'll notice one of the holes is completely covered. The seeds came in a 5 pack plus one of the issues I had in my first grow was banging around the plants when I was adding water everyday. I found that using one of the basket holes was a great way to pull water for PH testing and adding water without mucking with the plants.

Next is a view of the air pump. Boring, I know, but tucked up into a corner hopefully out of the heat of the light.

Last is a view of the whole closet. I plan on adding a second tank when more seeds arrive. Hopefully next week. One thing that may be visible is the closet has a tile floor and concrete walls. This is a basement closet and is fairly cool. I don't think heat will be a problem at all.

Happy Kitty

Well-Known Member
Best wishes for your grow, and welcome to the 420 community!

Peace and 420 :peace2:


New Member
Welcome to 420! :welcome:

I'm in for this grow. :popcorn:

Go to the Deep Water Culture Home thread (link in my sig). Introduce yourself and post a link to your journal. Lots of Deep Water Culture there willing to check out your grow.


New Member
Hi all,

Great news, good news and not as good news.

Great news: My shipment from Attitude arrived so I will be adding 5 more plants to this grow soon. I have Kali Mist, Laughing Budda, NYPD, and a ton of freebies. I decided to add 5 Kali Mist. It's the strain I am most interested in. I have read nothing but great reviews of this strain.

Not so good news: I need a second submersible water pump and my local hydro store stopped carrying them. WTF. So I ordered one from SH. As soon as it gets here I will add the second tank to the grow. I am not happy about having to wait for the second tank.

Good news: My black jack are sprouting. =)


New Member
Hi all,

Trouble in paradise. One of my seedlings (the "oldest") is yellowing.

The seedling is less than a week old. The others are still sprouting. One other is up through the rock wool but hasn't unfolded yet the others are sprouting but still in the rockwool. So at this point I don't know if it's just this one plant (isolated problem) or all of them (something wrong in the system). I should know in the next 12 hours as the others pop up and unfold.

Anyone have ideas? I haven't seen yellow sprouts this young. I am very concerned about having them stressed this young.

My PH is 5.6, I am using 1/4 does grow nutes.
::end edit::

Thanks in advance!
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New Member
Hey, bro.

1, did you use a pesticide on the floor and walls (I use Home Defense, safe for animals) to ward off spider mites. They are really attracted to high humidity and warm mosit places.
2, I don't see an oscilating fan.

The yellosing is due to something in the water that it doesn't like,
OR it is just hungry.

You could mix up a very weak nute mix, like use 1/16 of recommended dose, and pour it on the rockwool of the yellowing sprout .
just wait, it will be OK, it is just hungry.


New Member
Thanks RM!

No pesticides - just a serious vacuuming of the area and keeping a good eye on the space.

I grabbed my copy of "The Cannabis Grow Bible" and it agrees with you - not enough N. I will try your solution.

Thanks again!


New Member
A quick update.

My new water pump came in from SH. I started my Kali Mist soaking last night and will plant them this evening. All the equipment is soaking in PH 5.5 water.

The Black Jacks are not doing well. Something went wrong but I don't know what. Of the 5 planted only 2 made it out of the rockwool. They went in 6 days ago so I am about to give up on the three that haven't peeked their heads out. I will replace them with 3 NYPD if there is no sign of progress by tomorrow morning.

The two Black Jacks that did pop up are doing better. Thanks RM! The one that was yellowing is greening up already. The other is green and healthy looking. I bumped the nutes up to a half dose.

I also noticed the res temperature was higher than last grow. Last grow I didn't have any problems with the seedlings and the res was about 60 degrees. This time it is about 73 degrees. I had assumed the tile floor would help keep the tank cool, I don't think that's the case. I think the tile is being heated by the light and that heat is transferring to the tank. I put the tank on some paint cans to allow air underneath it and keep it off the tiles.

I also moved the air pump. While I had the pump itself hanging off to the side the tubing was exposed to the light/heat. I moved things around and the air pump is now outside the closet and there is only about 6" of tubing exposed. That 6" is in the shadow of the tank.

I'm a little worried that I am having issues this early in the grow. I didn't have any of these issues last time. But I also look at it as a chance to learn.

Hope everyone is having a great day.


New Member
Day 7 for the Black Jacks, day 1 for the Kali Mist.

I changed my mind about swapping out the dude Black Jacks with NYPD. Assuming all 5 Kali Mist sprout then I could have up to 5 female Kali Mist which would leave me with 7 plants. I grow just for myself and my wife. Seven plants is plenty of pot for the two of us. Even if I get some Kali Mist males I figure I will still have plenty to smoke. I am saving the NYPD seeds for the next grow.

First Black Jack A. She was the one that yellowed immediately. I followed Roseman's advice and here she is two days later:

Here is Black Jack B. The second seed to sprout:

Here is the closet with the new tank added full of Kali Mist:

I still need to clean up the cords and such.

Hope everyone is having a great day.


New Member

Everything is looking good. All the Kali Mist came up and are taking off like rockets. Deep Water Culture really does accelerate the early phase of growing.

Black jack - day 10.

PH: 5.6
Nutes: 1/2 strength Botincare pro Grow
Comments: Not a great picture (none of mine are). Two seeds germinated. One several days before the other. Both are visible in the picture but so is the size/age disparity. The larger plant already has a nice set of roots hanging below the pot.

Kali mist - day 4

PH: 5.7
Nutes: 1/4 strength Botnicare Pro Grow
Comments: All 5 seeds germinated. All very closely together. All the plants are the same size. Very very uniform. Healthy looking seedlings.

Group pic:

A couple of close ups so you all can see the seedlings more closely:

Any questions please ask.

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New Member
Im in, I got questions.

What is your room temp? And res Temp? With a MH bulb going in that type of room, I figured that would get hot.


New Member
Welcome to the boards my friend! Have you given any thought to using mylar on the walls? With the mylar you would gain some nice side lighting :)



New Member
Thanks RM =)

Great questions H6251686.

The room is hotter than my first grow and I am keeping an eye on it.

Room temp is about 85 degrees. Res temp goes between 72-75. Humidity is between 46-51%. I expect the humidity to drop some. It's been raining forever here and we finally have some sun. As long as it doesn't start raining again I expect the humidity to drop. If it goes too low I will add a humidifier to the room. I will also be adding a fan later tonight.

I am hoping the room doesn't get too hot prior to flowering. If it does I may move to a 20/4 schedule. Then once I go to a 12/12 having the lights off 12 hours should help keep the heat regulated a bit.

Push comes to shove I have an outbuilding I can move the grow to - I just don't want to take that step until it's absolutely needed.

Thanks all!


New Member
Oh good point SG - I still have some mylar from my last grow. I will hang it in the next few days. Just been lazy and they didn't really need it. Now that they're all above ground it's time to get serious.
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