Let's talk co2 and temps.

[ympb]

I'm running co2 with a temps from 79-84, RH 48-53%. I'm doing an ebb & flow with 4 floods a day in rockwool grow cubes (very hard to overwater). Res temps are about 73 (I'm in the process of lowering them to about 65-68, waiting in parts).

My girls are showing very minor signs of heat stress (a few leaves have flipped over but otherwise fairly normal looking).

Just wondering if any of you guru's can help me micro adjust for perfection. Any ideas, questions, or criticism is very welcome.

Thanks

 

[fred flintstoned]

Pictures would help. With CO2 injection, those temps shouldn't be a problem.
Fred

 

[ympb]

I'm currently running 2 600w lights on a light mover covering a 3x10 area. I think this is part of my streching problem. I'm going to switch out the 2 600's for 3 400's. I'm going to keep them on the light mover to help bring light to the shadows(and the fact that I've already bought and installed it...) My plan is that I'll get better coverage and the lights being 12-14" off the canopy will be less intense. I'm also installing a chiller and an 8' Ice box and fan on a day and night thermostat to help cool the room just a little when needed. I'm goin to put the intake for the fan at the exaust for my dehumidifier to help cool my biggest heat source in the room(fuck that thing puts off a lot of heat). The chiller will also be cooling my reservoirs with stainless steel drop in coil heat exchangers(I'll post pics of the progress).

 

[fred flintstoned]

Sounds like a solid plan. I'd get another 600 instead of 400 though. 3x600 will cover 3x9 without a mover. The turn down you see, picture 5? Not heat, nitrogen overdose. The beginnings of the dreaded rams horn. Over heating usually turns the margins up in an attempt to transpire more water to help cool the leaf tissue.
Fred

 

[ympb]

I agree with you on a third 600 but I don't really want to add another 600w to my power consumtion. Ive already doubled my power bill...and I'm getting ready to plug in a 1/3 hp chiller. Besides that I think the 600's are a little to close at 14-16" off the canopy and the actual width of the flood tables is only 2 1/2 feet. If I added another 600 and took out the light mover I'm afraid that the heat would curl them up like bacon. I can't go up or down with the lights or plants. I'm simply out of room. I've already purchased the new ballasts, I went with 400/600w switchable and i'm keeping my 600w bulbs so I still have the option to go either way(I told myself to buy these the first time).

I was wondering about a nitrogen overdose. I'm using Canna nutes and I have a quite a supply to go through still. Is there any way to thin it out? I'm using the lower end of the recomended dosage. 1.2-1.4 EC

 

[ympb]

Can i use less part of part A than part B with the Canna?

 

[Medi 1]

if your lights are that far away is why they are stretching. a 400 is only good for total 18 inches in penetration every inch more is half lumens. 600 is 22 inch and 1k is 24 inch. that total, not to tops of plants
you already have plenty of light for that erea. 600 on avergae does a 4x4 to 5x5 erea. no need for a mover even with 2 lights

your ec isnt as important as the Ph used to get the food in them. you can have a 4 ec and bad ph and it wont get any of the food.

 

[ympb]

I test and correct PH if needed daily. 5.6-5.9.

So what part of the plant should i be measuring to?

 

[bigv1976]

if your lights are that far away is why they are stretching. a 400 is only good for total 18 inches in penetration every inch more is half lumens. 600 is 22 inch and 1k is 24 inch. that total, not to tops of plants
you already have plenty of light for that erea. 600 on avergae does a 4x4 to 5x5 erea. no need for a mover even with 2 lights
QUOTE]
Who the hell told you that? The lumen measurment of a bulb is measured at 12" from the source. So at 12" you are getting full illumenation. At 2 feet away it is 1/4 as bright. It doesn't matter if is a 1000 watt bulb or a flashlight. So for a 400 watt light your plants would be receiving 55,000 lumens at 12 " or 13,750 if they were 2 feet away and then it goes proportionate to an inverse square from there. Check the attachment.

 

[ympb]

Thanks. That's exactly what I've researched. + rep

 

[fred flintstoned]

Can you cool the lights? I cool my 600s and the light is about 8in from the plants. No heat stress. In fact, sometimes they touch the lights for a day or so before I get to them, minimal burning, usually none. I use a 8in Vortex(747cfm) per three lights. They're cool to the touch.

you already have plenty of light for that erea. 600 on avergae does a 4x4 to 5x5 erea. no need for a mover even with 2 lights
What? Not even close. I think it's universally accepted, you need at least 50w per sq.ft. to grow cannabis. From experience, I can tell you 50w grows passable bud, not great. 600W over 3x3 is 66w per sq. ft. Much closer to the minimum to grow good bud. These measurements must take into account distance to the bulb. If you try to cover 4x4 with 600W, the outer edges will be real wimpy and the center will not grow to max capacity.

For the nitrogen problem, you can try adjusting the ratio of a-b to lower the N level. If you start to see other defs, adjust the other direction and feed at a lower ppm. Sorry I can't add much more than that as I have no experience with those nutes. I've used GH in the past, as well as a wallet lightening experiment with AN. I've used Dutch Masters for the last 4 years and am pretty happy with them.
Hope this helps,
Fred

 

[ympb]

I'm already cooling the two of them with a 440ish cfm fan. I only have 6" hoods at the moment so adding a third 600 would probably be pushin it.... My canopy measures out to 2.5'X10' so I'm at 48w per sq. ft. right now. I'll have options with the new ballasts that are on the way(600/400 switchable). I'm doing a perpetual so I may just leave the 600w on the final stage and trade out the other 600 for 2-400's. Any way I go I'm adding another light and don't have a problem with a 200w increase.

I'm having an exaust hood built by my local HVAC guy that I'm going to intsall over the dehumidifier that will draw the warm/hot air through an 8" fan and Ice Box that I plan on cooling things down a few degrees. It will be on a day/night thermostat that slows down and speeds up the fan as needed. I'm going to split the ducting for even distribution. I have a 6" Ice Box hooked up to my scrubber system right now that runs 24/7. It actually works pretty well being that I'm using a fairly ghetto DIY chiller. I'm interested to see how it all works out with a real chiller and bigger Ice Box and fan.

I'm fortunate to have 20 years in construction. This would be a super PITA if I didn't have a kick ass tool kit....

 

[ympb]

I was wondering if a non 50/50 ratio on the nutes would cause an explosion of some sort.jk
+ rep

Thank you for all your insight, it is very helpful. One can never have enough information.

 

[fred flintstoned]

I've been thinking about buying the ice boxes for a while. Seems the chiller and fans they require would cost less to run than my AC unit. Lemme know how the bigger ones work out, seems very few people around here have exp. with them and I never 100% believe a manuf. claims.
Natural skeptic I suppose, or maybe just a cynical old bastard with a shitty attitude.
Fred

 

[dieselboy]

I'm already cooling the two of them with a 440ish cfm fan. I only have 6" hoods at the moment so adding a third 600 would probably be pushin it.... My canopy measures out to 2.5'X10' so I'm at 48w per sq. ft. right now. I'll have options with the new ballasts that are on the way(600/400 switchable). I'm doing a perpetual so I may just leave the 600w on the final stage and trade out the other 600 for 2-400's. Any way I go I'm adding another light and don't have a problem with a 200w increase.

I'm having an exaust hood built by my local HVAC guy that I'm going to intsall over the dehumidifier that will draw the warm/hot air through an 8" fan and Ice Box that I plan on cooling things down a few degrees. It will be on a day/night thermostat that slows down and speeds up the fan as needed. I'm going to split the ducting for even distribution. I have a 6" Ice Box hooked up to my scrubber system right now that runs 24/7. It actually works pretty well being that I'm using a fairly ghetto DIY chiller. I'm interested to see how it all works out with a real chiller and bigger Ice Box and fan.

I'm fortunate to have 20 years in construction. This would be a super PITA if I didn't have a kick ass tool kit....

is the dehumidifier really neccessary? just wondering, i dont use one unless i feel i have to. and i agree with whoever else said it, 2x 600?? thats more than enough light for 3x10, especially if your worried about electricity bills.

 

[ympb]

An AC unit is just not the ideal set-up for me...I looked into it every possible way. Besides that I built a distribution manifold and will be using coiled stainless tubing to get my nute solutuion to about 65 degrees.

BTW My cooling system probably cost me about 1500.00 or more....I will keep everyone informed on how it works.

 

[ympb]

is the dehumidifier really neccessary? just wondering, i dont use one unless i feel i have to. and i agree with whoever else said it, 2x 600?? thats more than enough light for 3x10, especially if your worried about electricity bills.

My humidity was in the 60-70% range. Trust me. I didn't want to buy or pay to run one....but now I dont have to worry about all that mold crap.

 

[Medi 1]

big v...the manufacturer tells us at pour shop this spec on closeness. but i guess they only make them and know nothing on how to use them. ive seen to many diff specs on them inverse laws. seems some make their own up. not saying that one is wrong but ill go with how my manufacurer tells me to use them.
also ive tested it with a meter.