1st Grow: Indoor Tent, 250W MH/HPS, DWC Hydro, 2'x2' ScrOG

[lovethestuff]

They grow fast, don't worry. I thought about doing a journal, not sure yet! second time for me growing hydro, last time was about 10 years ago, mostly soil outdoors for me....600w hps, ebb n flow, fax farm nutes...

[ultrasonic]

I was thinking more about your PH issue, and I think alot of it might have to do with your small res. I use rubbermaid roughneck hightop bins, and they hold (oh gosh I can't remember right now...) about 14-18gal of nutrient solution.

6 gallons is very little to work with, and thats probably the source of your issue, along with a possible source of contamination (because of algae). Did you soak your rockwool well in ph balanced water? If you didn't, this is most definately the cause of your ph swing.

Let me know whats been going on, stay safe.

[usul]

Looks like I've found a solution to the pH problem - details below... First, today's stats:

Days Vegging: 8
Air Temp: 77F
RH: 39 - dropping below the minimum - might have to do something about this
Water Temp: 68F
pH: 5.6 - 5.9 - stable with no adjustments needed
TDS: 450ppm - continuing the steady climb to full strength at around 1500

Thanks for the support everyone and thanks for tuning in! I promise not to disappoint and if the last week has been any indication, there should be plenty of drama to come.

Okay, here's the latest: One day after the last res change pH was, again, unmanagable. The water was cloudy with white foam building up around the edges. Research indicated it could either be algae or bacteria. More research shows the only thing that can manage the problem without killing the plants is Hydrogen Peroxide (H2O2). I gave the res a well-measured squirt and after about 4 hours I could see improvement, but the enemy still had the upper hand so now that I had a weapon that worked it's all out war!

I pulled the plants and put them aside in a safe place, drained the res and pulled everything out of the tent. Tossed the air stones - there's no way I could get those completely clean. Everything else got a serious scrubbing with strong chlorine solution then another scrub with strong H2O2 solution. Added new air stones and tubing and took the opportunity to upgrade to larger stones and a better pump (the one Stealth Hydro sent is crap). Next, I mixed up a new batch of nutes. Buffered the pH and this time added H2O2. The res will also get a daily dose of H2O2 as well, all on an application schedule I derived from several sources.

The results: I pHed the nutes to 5.6 and after over 24 hours it has climbed to only 5.9 with no adjustment whatsoever! The plants didn't like getting moved around but now they are loving their new home. They look great and are growing noticably faster. I'm not ready to declare victory yet, but if I'm able to keep pH in the zone (5.5 to 6.5) adjusting it no more than once a day and don't have to change the res for a week I will be victorious. If everything works I'll post my H2O2 application schedule along with the pH buffering technique a little later.

What I've learned:

1. I think the infection problem came from using tap water for the first batch of nutes. I've read about some growers having success with this so thought it was worth a try. Bad idea.

2. DWC Hydro in a small space is very challenging. Ultrasonic: your comment about getting a larger res is very wise and I'm sure it would help - I simply don't have the room. Munki also made a comment that temperature control of the DWC res is both critical and difficult, epscpecially in a small tent. As a result, this grow is becoming expensive! Ultrasonic, I think you mentioned you've spent about $2K for your 4x4 setup. I've spent about $1.5K for one quarter the space. There's no way I can go bigger so I'm not complaining, and once I get this all dialed in and optimized it will be a thing of beauty. Miniaturization is never cheap.

Here's the latest pics of the young ladies - 8 days old. Sour Cream has yet to show any roots so I'm a little worried about her but she looks healthy and is growing strong. Roots are sure to show soon.



In our next episode: I'm about to pull the High Output Flourescents and install the 250W Metal Halide. Temperature control will be the next challenge and I'm up for it! Temps under the lights are currently 77F and I'm only using about 10% of my cooling resources - haven't even turned on the big exhaust fan yet. And I have a few aces up my sleeve

Stay tuned...

[Caddie]

Great information usal. This is exactly the type of grow I like to follow. Except I'm using soil and 1000 watts. Great info on cleaning out you DWC system. Things should go better from here I hope.

[WheeloFortune]

hey usul, looking good. your doin great work with the pics, love the labels!

two things,

in your first post you said you are using a GH run to waste?!?!?!? but DWC is not run to waste! it is most def recirculating, even if you change it often. i would double check your nute schedule and find a recirculating one for your nutes.

also, if money is not a concern, i think you said that before and man what a good thing to be able to say, but if it isnt, most definitely get a chiller. . . it will maintain your res temps to the exact degree which is huge in DWC because temps directly control DO (dissolved oxygen). this is one of the best things you can do to make sure you have a healthy root system, and then everything else will be gravy baby. if you don't have healthy roots, you wont have big buds. . . also lower temps will help control any nasty bacteria, as they dont like it very cold.

right now you say your res temp is 68, if it stays under 70 your good, but i doubt it will when you get the 250 going, and the tent closed.

i'll be around bud, good luck.

[usul]

Thank you SO MUCH Wheelo. Your reply illustrates why I am on this forum and why this community is so great.

I have found the recirculating schedule for my nutes and am recalculating. Looks like I'll need to add more - good news as that'll give me more pH buffering.

About res temps, yes, it is my greatest concern. I have a chiller queued up and will bring it online if needed. That said, once I fire up the exaust fan I'll be drawing in a lot of cold air from under the house and it cools the res first. Should be interesting to see how it works out. Stay tuned folks...

[WheeloFortune]

good deal Usul,

if you have a chiller in the que (like me) you are sitting pretty. . . i'm not using mine either because my res sits at 68* with no help right now, so its a waste of watts.

you have some killer strains there, so you should be really happy with your investment when it finall pays off, but just be forewarned you have a ways to go. lol.

how long do you think your going to veg?

[usul]

Originally Posted by WheeloFortune

you have some killer strains there, so you should be really happy with your investment when it finall pays off, but just be forewarned you have a ways to go. lol.

how long do you think your going to veg?

Thanks WheelO, - a long way to go for sure! The switch from veg to flower seems like a lifetime away. This really is my first grow ever and every day is a learning experience - it's hard to think past tomorrow!

Regarding the timing question, what do you think? Conventional wisdom seems to say 4 weeks. I'm going to ScrOG so I think timing will be determinied by how full the screen gets? I was thinking when it's 50% full I'd screw in the HPS and go 12/12. Are you familiar with these strains? Should I expect a lot of stretch?

I'm also wondering how far the screen should be from the top of the res. Vertical space is tight: I have 28 inches from the top of the res to the bottom of the light. Any and all thoughts appreciated!!

Meanwhile... plants are happy, pH is stable and upgrading to the 250W light is under way <...sound of saws and hammers in background...> I'm working on a somewhat unique solution to the cooling challenge - should be able to test it later today.

[usul]

The 250W Metal Halide is blazing away and I've brought a new cooling system online. First, of course, today's stats:

Days Vegging: 10
Air Temp: 77F
RH: 39 - still a problem - just added a humidifier, I hope it helps!
Water Temp: 64F - is this too cold?
pH: 5.9 - very stable
TDS: 450ppm

I decided it was time to transition from the Flourescent lights to the Metal Halide and, in my tiny tent, I figured this would create temperature problems. I was ready to buy a chiller but thought I should try a simpler solution, and it worked! Instead of spending $300 on a chiller installation I met the challenge using <drum roll...> a $2.50 piece of styrofoam.

In a nutshell, I divided the tent into two chambers: one for the plants, one for the res - separated by a barrier of 3/4" foam insullation. Cold air from the crawl space enters the res chamber and a baffle channels it around the res before entereing the plant chamber. Here are some pics:





The old circulation fan (the one that didn't work with the timer) was replaced with a pair of EcoPlus 4" axial fans - those little suckers move a lot of air! One is on the same timer as the light, is aimed up at the light and moves air around the plant chamber. The other is on the same timer as the exhasut fan and is in the res chamber to boost cold air flow. The system has been running for three hours now and res temps have fallen from 66F down to 64F. Is that too cold??? This is certainly not a problem I thought I'd have. I may need to shut down the booster fan or put it on a timer.

Otherwise, the Ph issues seem to be very much under control. It's up to 5.9 but I haven't had to adjust it in nearly two days.

Other than the res perhaps being too cold there are two issues that cause me concern:

1. Humidity is way low. It has gone as far down as 30%. I've added a small humidifier to the plant chamber but it doesn't seem to be helping much yet. What sorts of issues will I encounter with low humidity? I hope this will be less of a problem once there is more foliage in the plant chamber.

2. The plants are perky and seem to be growing well, but their color seems very light to me. My first thought was that they are not getting enough nutes, but the res TDS is 450ppm and that seems about right for plants this size. I'm going to let it ride for now and keep a close eye on it.

Here's the latest picture of the girls at 10 days old.



As always, any feedback, thoughts, insights and guidance are very much welcome and appreciated.

[Caddie]

Damn Usal, you have a very informative little grow going on here. I love your photos with the the arrows and info. That is very informative.

I've got the same humidity problem you do--but I have a small grow like yourself right now. My plants seem to be about the same age as your's. I'm not too, worried about the RH right now.

I think it hurt my seedling stage, but I think they are doing fine now. I think plants would rather have low RH than a high one. I'm really surprised you can't keep a higher RH in your box. You must have great ventilation--which is great.






I'll keep watching your grow, and I'll let you know when I start my journal.

[usul]

Quick update: After lights-on for about 12 hours the res temp had dropped to below 60.5F. Air temp has remained steady at about 77F but the plants do not look happy. A few hours ago I shut down all but the large exhasut fan, pulled my fancy styrofoam thingy and lowered the light a few inches. Res temp is climbing slowly...

I'd really appreciate some feedback on the low temperature issue. Perhaps the plants are just reacting to a sudden drop in temperature and they will love it in the long run? Or perhaps I should buy a res heater? Interesting problem and certainly not the one I thought I'd be dealing with.

p.s. Sour Cream is still not showing any roots and is lagging in growth. She may not make it...

[ultrasonic]

Originally Posted by usul

Quick update: After lights-on for about 12 hours the res temp had dropped to below 60.5F. Air temp has remained steady at about 77F but the plants do not look happy. A few hours ago I shut down all but the large exhasut fan, pulled my fancy styrofoam thingy and lowered the light a few inches. Res temp is climbing slowly...

I'd really appreciate some feedback on the low temperature issue. Perhaps the plants are just reacting to a sudden drop in temperature and they will love it in the long run? Or perhaps I should buy a res heater? Interesting problem and certainly not the one I thought I'd be dealing with.

p.s. Sour Cream is still not showing any roots and is lagging in growth. She may not make it...

Hey man, sorry so long to get back to you: Get a fishtank heater for that sucker! 20 bucks. that way you'll know you'll never get too low. Now that winter is starting up here, I think I may even be in the same shoes. My res which normally runs at 72-77F is currently 61F!

ps- about your photos - love the labeling. Reminds me of biology class in highschool - I loved drawing those diagrams of cells and "properly labeling" all the parts, lol

Good Luck! I'll be posting my update tomorrow because today I got ahold of my bulb company, and will be thankfully talking to the good guy tomorrow.

[usul]

Looks like I have the res temp issue under control. I am such a newbie - every day is a learning experience. Here's where I'm at:

Days Vegging: 12
Air Temp: 77F (it'll max out at 81F)
RH: 45 - the humidifier is working, but just barely
Water Temp: 68F - got the res temps up but this may not last
pH: 5.7 - stable - no sign of the enemy
TDS: 325ppm - I got ahead of myself and had to had to back off on the nutes.

Hey Ultrasonic! Thanks for stopping by. Once again, you have provided some comfort sharing that your res temps had dropped nearly as far as mine. We may be the only two growers on the planet with this problem. I can find hundreds of articles about the res being too hot, but not a single one about it being too cold. I wonder how cold we can go? Research indicates a 60F res has more available O2 than one at 65 or 70. But would a res that cold be bad for the plants? C'mon all you experts out there - this is why I'm on this forum - what do you say?

Anyway, I've continued to lower the light - now at 12" above the plants. That, combined with pulling out the heat barrier has brought the res temp back up to nearly 68F. That said, as the plants grow and the light will have to go up and the res will cool. That res heater may come in handy - if needed.

Last thing: I have to confess I made the classic newbie mistake: I overdid it on the nutes. I was worried about the light green/yellow leaves and upped the TDS to 570 - and the leaves started curling down. They're not curling under and there are no brown tips but I'm fairly sure this slight deformation is over-nute related. Experts weigh in please! I added fresh water taking TDS down to 325 and LA Woman responded positively. Sour Cream is stilll having a bad day. We'd all be much happier if she'd just grow some damn roots. Anyway, this is why the plants are looking droopy now. Live and learn.

Here are the latest pics. Happy to hear so many of you like the labels :) I was a graphic designer in my previous life and did a lot of technical publications. Then I did 10 years in Web site design so posting an image without fooling around in Photoshop is almost unthinkable. Crazy me.

[ultrasonic]

Hey Usul how goes it all.

Babies are coming along there! It's one day at a time, lol.
So - I wanted to get this out there: you're using the GH line of nutes? you're not using that miserable green shit are you?

If you don't know about it already, i'm going to rock your world. It's called the lucas formula. It uses GH nutes, but only the micro/bloom. It's a simple ratio: 5micro/10bloom for under CFLs, or 8micro/16bloom (the newer recipe) for HID lamps. What you've seen me use is the 5/10 mix. Oh yeah, thats all PER GALLON of RO water. Do some reading on that, I would HIGHLY recommend it.

So aside from that, the fishtank heater is a good idea I think. They really aren't that expensive, and have set-points so they don't heat forever. I may have to go that route for my now-flowering mum, but maybe not.

So your plants are growin' good man, they look a little angry, but if you're using GH nutes without lucas forumula, that could be why :) They really love that mix. Also, that light green isn't really an issue potentially. It could be mostly because the roots are taking in nutes now so there is a growth explosion. New growth will always be really pale. It also could be strain specific - some are very light green. (reminds me of a police chopper pilot Interview I saw once saying how easy it is to spot MJ plants in the sky because they don't look right... Fluorescent green compared to the other growth. He mentioned a strain of BC bud I think that they have trouble detecting because it's such a dark green color, it blends really well.)

Anyway! more luck to you, look forward to seeing some big plants :)

[Hydroguy]

Hey Usul,, great journal,, will be watching with interest.

ultasonic had is spot on about your prev ph problem, rockwool will force ph up for the first week or two, also you have a small res so will be more dramatic then most.
To combat this when i add fresh water (daily) i ph it down to 5 (for the first week)and that offsets the ph jump.

great job,, reps