CFL / Fluorescent Lighting
12/12 from seed, stealth cab, SCROG grow in the
Indoor Growing forums; On 6/19/12 i put eight seeds of three different strains into MG organic soil with MG perlite mixed in. Its ...
12/12 from seed, stealth cab, SCROG grow
On 6/19/12 i put eight seeds of three different strains into MG organic soil with MG perlite mixed in. Its now 5 days in and still no plants sprouting out of the ground but should see them come up pretty soon. This is going to be a 12/12 from seed grow and i have a screen placed in the cab for the SCROGing later on. right now there is only one 24w cfl in the cab for the seedlings but i can put three more in once they get bigger and i can get more air flow into the cab. Im having heat problems and im not sure why, i have 4 computer fans pushing fresh air into the cab from the bottom and coming out of the top. with a fan inside the cab circulating air. I want to put another computer fan in as exhaust also. I planted 8 seeds and i hope to keep at least 2 of the plants in the end. Once they need nutrients I have 2-7-7 MG cactus food nutes. also i will be feeding small doses of a honey/molasses mixture every three or four waterings later on. Also the inside of the cab is lined with milar for reflecting the light. Does anyone have any ideas on how to bring the heat down inside of the cab? Right now its at 85 with only one light. The ambient temperature is between 65-70 degrees.
2nd to sub
you might have too much intake and not enough exhaust??? Looks good I like the cab... how big are the pots you're going to use for final product??? stay high
Ummm thinking some solo cups, depends on how many plants are left in the end. if theres three or less im going to use larger containers then the solo cups. and yea i was thinking that there was not enough exhaust also. so im going to make the spot where it comes out bigger, and throw a PC fan over it to push more air.
good thought you want more exhaust than intake... negative pressure is important. stay high
Originally Posted by ҖҗlegilizeitҗҖ
whats the advantages to positive or negative pressure? because right now my cab is really positively pressurized.
you know I had some great info on this on my notepad... which is no longer there...
basically you are exhausting more air than what is coming in. in fact you can do no fans for your intake (known as passive intake). this can help to lower temps and humidity in your cab... the one thing you want to becareful of with negative pressure is to not over work your exhaust fans... you want a 2:1 ration exhaust to intake.
With too much intake and not enough exhaust well you are just cirrculating the warm air in the box and not getting rid of all of it... am I making sense?? hope this helps. If you need more info about this let me know stay high.
yeah i kind of get what your saying, but if the fans are pushing in air and at the top theres a hole where i can feel air flowing out of, isnt that working? or is just way more effective to use exhaust fans?
always better to have more exhaust than intake... imo... exchange rate is important... you want to exhaust a certain amount of air per 5 min intervals. so cfms is important... here is a post i did a while back
To control excessive heat build-up a ventilation system must be incorporated. This can be done simply with fans, or a carbon filter/fan combination that will clear odor and sterilize the area at the same time. Ideal Grow Room temperatures should be between 65*F and 75*F. If temperatures rise above 85*F your plants will begin to suffer from excessive transpiration, which is the loss of crucial water held within the leaves and stem cell walls. Another factor that ventilation will help control is the relative humidity level or RH of your growing environment. RH can also have an affect on transpiration. Proper humidity levels range from 45%-65% RH. A Thermometer/Hygrometer is a must to maintain proper levels. Some General Tips:
• Lighting systems generally consist of four components: ballast, cord and socket, bulb and reflector. A 400 watt lightwill cover a 3x3 or 4x4 area, a 600 watt will cover a 4x4 or 5x5 area, and a 1000 watt can usually cover up to an 8x8. Remember the more light you have, the more the plants can feed, thus photosynthesize and produce a fruitful yield.
• When air cooling lights, use at least 250 cfm per 1000 watts. (I THINK THIS SHOULD BE CLOSER TO 400CFM TO COOL LIGHT, just my opinion)
• Generally it’s a good idea to use 3000 btu of cooling energy per 1000 watts.
• Typically, you will want to exchange the air in your grow room every five minutes. To figure this out use the formula Length x Width x Height = Cubic Ft, then Divide by 5 to get your recommended CFM (Cubic Feet per Minute)
(Example 8ft x 12ft x 8ft = 768 divided by 5 = 153.6 so you would need at least a 153 cfm fan to exhaust your room)
Using Carbon Filters:
Carbon filters are great to use in your grow room. Since you need an air exchange any way, why not sanitize your room in the process? Match the CFM of the filter and fan, attach it to fan intake, and you are ready to go. All carbon filters have a recommended CFM; it is important not to exceed the recommended CFM as the filter will not sterilize the air properly. When mounting your carbon filter it is best to mount the filter high in the grow room to allow any hot air to be filtered first. If mounted and connected properly your fan and filter will accomplish three things:
• Act as an air exchange in your grow room
• Decrease the temperature by taking out hot air
• Sterilize grow room killing mold spores, pathogens, and deodorizing
Hope this helps!!! Stay HIGH!!!
thanks man. yea that was helpful, im deffenitly going to try to add like two exhaust fans at the top of the cab and see how much that helps, still wil be positive pressure in the cab with 4 intake to 2 exhaust but there will be some great air flow
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