Air Cooled Lights Questions

[Gobwats]

I'm expanding to where I will have a separate flowering room that I want to light up with a 400w HPS lamp. I have been thinking of going with an Ultra Cool XL reflector with a 6 inch flange. First question, has anyone used or know anything about this reflector (I have searched Pico's excellent thread and could not find a reference to it there) to know if it's a good choice.

Second question deals with the fan; I know it is better to pull than to push the air, and there really is no such thing as overkill, but just how many cfm's do I need to keep a 400s HPS lamp cooled. This will be an independent system, so I was figuring on having the fan run the entire time the light is on. I'm planning on tying the exhaust into the rest of my exhaust system, but have no clue how to arrange the intake; should it be pulled through a cheap filter or just open ducting?

Current garden is in week 6 of flowering, so I want to have everything figured out and ready to go together as soon after harvest as I can. Definitely appreciate any advice offered this way.

 

[FreezerBoy]

Try running your numbers through this fan-intake calculator

You'll want some sort of filter for intakes if only to keep out bugs. People use cheesecloth, coffee filters, pantyhose. I use aquarium filter pads

 

[Gobwats]

Many thanks FreezerBoy. I figured some sort of sock to keep the trash out, but was curious if running a HEPA filter, like I do on my intake for the room, or something to that effect might make a profound difference to justify the expense. If not, I see a great use for stretched out tube socks, lol.

The chart is great, thanks for pointing me in that direction which is what I have spent the past couple of days searching for prior to posting. If I'm interpreting it correctly, using a 400 cfm fan my light would be raising the room tenmperature 3-4 degrees above ambient which I could easily take care of with my intake/exhaust?

Finally growing some fancy hybrid seeds with this grow (been a bag seed farmer all my life, what can I say, I'm an old hippie...good to have friends who care in the business, lol) so I'm aiming for the perfect setup after perfecting my hydro technique with the earlier gardens.

 

[FreezerBoy]

curious if running a HEPA filter, like I do on my intake for the room, or something to that effect might make a profound difference to justify the expense.

You're way outta my league here. While I obviously blocked a lot of dust and dirt, my concern was keeping bugs out of a nurturing, predator free environment. I've no idea what effect a HEPA filter has on a plants growth or trich production.

 

[Gobwats]

You're way outta my league here. While I obviously blocked a lot of dust and dirt, my concern was keeping bugs out of a nurturing, predator free environment. I've no idea what effect a HEPA filter has on a plants growth or trich production.

They make great dust collectors, lol. I can see using them on my room intake to give the plants the cleanest air possible. Going to that extreme just to cool a lamp seemed a bit much though, so thought I'd pose the question while I'm in the process of putting everything together. My grow room is in my office which grows dust somehow (you should see the filters before I clean them) and HEPA filters can be cleaned and used forever so I'll keep using them for the intake to the rooms, but go with something like you mentioned for the light setup. Many thanks once again my friend.

 

[Hydro-Soil]

Going with a 400w HPS will also give you the option of going to CMH bulbs later on if you like. (as long as your ballast is magnetic)

 

[Gobwats]

Going with a 400w HPS will also give you the option of going to CMH bulbs later on if you like. (as long as your ballast is magnetic)

Went digital on the ballast, so it supports both HPS and MH. This originally was going to be a separate flowering chamber, but the cost on that got a bit beyond my means so I opted for an upgrade to the existing growroom. I'm currently growing under CFL's and while they are effective, I'm tired of seeing all those lower buds that will never achieve their full potential; great upper buds with it but no matter how many fan leaves I prune back, it just does not penetrate deep enough. So I'll probably use MH for my vegging and use my CFL's and T5's for mothers and cloning.

 

[FreezerBoy]

NOT trying to keep you on CFLs but, your mention of penetration requires I ask. Have you checked out LST and ScrOG? By growing horizontally with ScrOG I kept my 19 inch colas to 6 inches in height.

 

[~fvk~]

I use 125 silk screen on my intakes. I don't know if it's enough to keep spider mites out but I haven't run into any yet either. I know it keeps fungus gnats out but it don't stop them from finding their way into my grows. I suppose it wouldn't be as good at filtering allergens and stuff compared to aquarium filters or carbon sheets but I like using the silk screen over pantyhose AND 3M allergen filters. Pantyhose got ate through by Japanese beetles and the allergen filters restrict too much airflow.

 

[Gobwats]

NOT trying to keep you on CFLs but, your mention of penetration requires I ask. Have you checked out LST and ScrOG? By growing horizontally with ScrOG I kept my 19 inch colas to 6 inches in height.

Have played around learning both techniques. I like to start them flowering when the plants are about 8in, that way they finish at the max height my grow room allows for. I've been using 2 125w CFL's up top and 5 55wHO T5's up the 4 corners. The CFL's are great for early vegging, and if I ever get things set up like I really want (separate chambers for vegging and flowering) I'll be back to starting them under the fluorescents. I just hate seeing all those low buds that get enough light to form, yet not enough to fully develop. I revegged a couple of plants last grow for clones which gave the lower buds a chance to mature and they were killer.

 

[Gobwats]

Got another question regarding air cooling of lights (been sick so everything is sitting here still waiting to be hooked up.) It's more efficient to pull the air rather than push it, but does it make a difference which end you pull it from? I'm thinking if the fan is drawing from the side where the socket is it will be closer to more of the heat source, thus should be more efficient. My undergrad chem and physics texts have long since been packed away, so can some of you thermodynamic experts offer some advice, even if it's only to tell me to stick to theoretical mathematics?

Current grow I think I'm going to let finish under the CFL's. I'm seeing more red hairs every time I look in there (currently midway through week 8 of flowering) so I'll probably start flushing them for harvest next week.

 

[panopticist]

What kind of ballast are you using?

I've got a 400w Galaxy and the YieldMaster 2 6" AC reflector. I keep things cool with a 6" Vortex dialed down to half speed. It keeps my Homebox L at 72° F with lights on.

I push all of this air through a Can Filter 33 with no issues whatsoever.

You'll definitely want some sort of prefilter material over the open end of your reflector. Something along the lines of pantyhose or cheesecloth. I'm personally going to move up to FreezerBoy's aquarium filter pads.

 

[alegoblin]

Hey Gob just my two cents.I am using a 4" 180 cfm in line to push across two 400 watt diy cool tubes.This is mind you completely independent from my intake/exhaust system. IMHO pushing from near air source is mo better.I am pushing about 16' with good hot exhaust at the out end. Pulling hot air through your fan will definitely shorten its motors life.Good luck with your grows brother.Peace,Ale.

 

[B00st3d]

you def dont need the high output 6 inch fan, just get a regular 6 inch. I like the can fans but my vortex is my fave. If its only gonna be on 12 hours a day then you can with a less expensive fan then the cans. Avoid the cheap Active Air fans, they are junk. If you were using it for veg and it was on 18 or 14 hours then Id say get something like a can of vortex. I use vortex on top of my can filter since its on most of the time, had it goin for a few years and its still as quiet as it always was, works perfect. I use a blue hepa filter on my intake and then a backdraft damper on the exhuast side so when it shuts off no light can creep thru there into my dark flowering room. The backdraft damper is cheap and well worth it. When the intake hepa filter gets dirty just vacuum it and its perfect. If you dont wanna spend a hundred bux on the hepa then use the filter pads as mentioned above. But the hepa filter will never need to be replaced btw.