mogie
Well-Known Member
Ventilation
I am fortunate in being able to punch holes right through the outside wall to bring fresh air into the space. I drilled two 3" holes with a hole saw in the bottom of the lower flowering cabinet, and installed a short section of 3" PVC drain pipe through the wall. On the outside of the wall I mounted dryer vents with the air inlet pointed down, and a screen mounted to keep bugs out. I painted the PVC tube and the inside of the vents with flat black paint to limit reflected light. Amazingly enough, the bright sunlight is only 3" away from the dark interior of the cabinet, and I have no problem flowering.
On the inside, I clamped fabric shop vacuum bags over the ends of the PVC tubes, which protrude into the cabinet a bit for that purpose. The vacuum bags keep the "borg" out (mites), as well as stray pollen from unwanted male suitors growing outside in some neighbor's back yard [or clouds of hemp pollen from Canada! - ed].
Moving over to the first cabinet stack, the mother compartment is serviced the same way, but I only use one 3" opening. Airflow from the lower flowering cabinet next door is sufficient as an inlet in the upper flowering cabinet, but I did add one 3" inlet for use in summer, when some additional cool air is welcome.
I use 200 CFM Dayton squirrel cage fans both in the mother compartment and the upper flowering compartment. If we're designing a system with three flowering cabinets, I would use one in each. These fans are compact, easily mounted with integral tabs flat on a wall, and they are efficient and quiet. The big Dayton may be a bit of an overkill in the mother compartment, but it's easier on the mechanicals to use a large fan on now and then vs. a smaller fan huffing away all the time.
The fans have a square outlet tube that fits into nothing I am aware of; why do they do that? In any case, I stole the aluminum tube that comes with the dryer vents I use, flattened it out into a sheet and molded it into an adapter, converting the square hole of the fan outlet into a circular opening to insert inside a piece of flexible dryer outlet hose. I just used duct tape to strap the whole mess together. OK, it's not very sano, but it works.
What about CO2? There is little room for the mechanicals, the scrog blanket will already get as thick as it can be, and the fans are on quite a bit with the hot lights in the enclosed space, and would blow out the CO2 regularly (every five minutes or so). So, I doubt it would be useful in this limited growing situation.
The outlet is also a 3" PVC pipe punched through the wall. The inside protrudes into the cabinet as a place for the flexible dryer conduit to be clamped. The outside outlet is another dryer vent, with the flap pieces left in place to prevent insects and debris from floating in through the outlet tube. I ran the outlet right out through the eave line in the soffit, where it exhausts into some bushes.
What if you don't have the luxury of being able to tap the outside air so easily? Well, you can draw air from a crawl space if there is one below the cabinet, by running 3" PVC tubing up inside the cabinets to the desired compartment. If you use Rubbermaid 11 gallon containers mounted sideways, there will be enough space in back to run several such conduits. I ventilate the mother cabinet like that. The same holds true for the outgoing air. The fan can exhaust down a 3" PCV pipe into the crawl space, and flexible tubing can carry the air to the nearest available hidden outlet. You can't run air through tubes that are too long, or the fan won't be able to push the air needed. But I have tested a run of over 20' with no problems. I didn't use it, but the fan moved the air easily.
Controls
The fans need to be wired up to thermostats as controls, a humidistat too, if you can afford it. I use both, but I find the humidistat wasn't needed, as there is frequent enough airflow through the cabinets to avoid high humidity.
When selecting a thermostat, I recommend you avoid cheap units and get something decent. I use the industrial gray Dayton units with the exposed black coil. Damned expensive, but they work very well, keeping the temperature within a range of a few degrees from the setting. I used cheaper units at first, but the things allowed the temperature to fluctuate all over the place, and I ripped them out in disgust.
We want to mount the thermostats up high in the cabinet, where the buds will be growing, as that is the airspace that is critical. Generally a temperature of 70-75 degrees is recommended, and the combination of the Dayton 200 and the good thermostat nails it on the button. I sound like a commercial for Dayton products. Little do they know... [I bet they know perfectly well! - ed.]
All the lights and pumps are controlled by cheap hardware store dial timers, which I plug into wall sockets I built into the cabinet walls. These timers are junk, but have failed on me only once (costing me an entire mature Durban sea of green crop while on vacation, you bastards!). I have considered more expensive, and presumably reliable, timers, but haven't done so yet. Although the ballasts are by themselves in a separate compartment, they started off sharing the flowering cabinet space, and the outlets and timers are all still located there. That means I have to run some power cords from the timers through the walls into to the ballast cabinet, but it doesn't look too messy; there are already cords coming from the ballasts to the light hoods.
The reservoir cabinet has its own outlet and timer. I run the pumps for both reservoirs and the air pump from a single timer.
Water
The bottom compartments hold the reservoirs, and 11 gallon Rubbermaid storage containers work great. They will be in the dark, but it's not a bad idea to wrap them in black plastic to keep all light out, which prevents the growth of algae [also for the growing containers, of course - ed]. Cut out a window to check for water level of course. I use submerged Little Giant type pumps. The 8' compartment stack requires a pretty hefty pump, as there is quite a vertical distance for the water to climb. The pumps show how high they can push water on the side of the box. Again, go more robust than you need to provide a cushion.
1/2" drip system tubes work fine to deliver the water up into the cabinets, but you can also use hard-wired PVC plumbing bits and pieces, and there are adapters to mate the two. If you use PVC, go 3/4" to allow the water to mix with air on the drain leg. I used 1/2", but would go larger if I was starting over.
The water needs to get from the plant containers back down into the reservoirs, and gravity handles that. There are myriads of ways to plumb the system. I choose open drain holes cut into the floors of the compartments. I use Rubbermaid containers to grow in, and mount a cheap chrome sink drain in the bottom of the containers (more hole saws to buy). The chrome drain piece sits in the hole in the floor and drains into a large PVC adapter fitting that is plumbed into the drain system, all connected together and flowing back into the reservoir below.
For a long time I relied solely on the action of the water splashing down the drain tubes and into the reservoir to aerate the solution, and it works fine. But when I added the second flowering cabinet next door, with its own reservoir, I lost that effect due to the short distance the water falls. So recently I added a good quality aquarium air pump connected to an airstone in each reservoir.
Every couple of weeks the reservoirs need to be drained, and while you're plumbing away here, add a fitting to the cabinet to connect a hose, plumbed into the pump outlet line. That way you can connect the hose, turn on the pump and allow it to drain the tank to the outside. The hardware store is an endless source of valves and connectors to fulfill any elaborate design you like, to get water in and out of the reservoirs. I plumbed in valves in each compartment as well, so I can isolate one compartment from the water system during maintenance, etc.
Water is added to the reservoirs with a 1/2" drip tubing piece connected to a quick connect hose coupling. The drip tube piece pokes through a hole drilled in the container top (yes, another hole saw to buy). Filling up is clean and easy. Nutrient mixes are added from a jug with a piece of the same 1/2 drip tubing mated to the top. As I mentioned above, I plumbed in a valve and outlet in the line from the pumps in order to use the pumps to drain the reservoirs out through a hose for changing the water. I do so every two weeks.
Vacations present a special problem with such small reservoirs. To avoid having a friend or two watch over the grow (the less people who know, the better), I added a McMaster Carr brass float valve assembly to the Rubbermaid raised lid. That could be connected to a hose, but the consequences of an open hose leaking or a connection breaking gave me the shivers. Instead, I bought a 30 gallon storage container as a supplemental vacation reserve. I place it on a shop table and it gravity feeds the McMaster Carr float valves. If it blows up, I will only have 30 gallons leaking, not the contents of the entire Seattle water system. I don't normally use the float valves for water input, as they maintain the water level a bit below full, due to the clearances involved with the float.
I am fortunate in being able to punch holes right through the outside wall to bring fresh air into the space. I drilled two 3" holes with a hole saw in the bottom of the lower flowering cabinet, and installed a short section of 3" PVC drain pipe through the wall. On the outside of the wall I mounted dryer vents with the air inlet pointed down, and a screen mounted to keep bugs out. I painted the PVC tube and the inside of the vents with flat black paint to limit reflected light. Amazingly enough, the bright sunlight is only 3" away from the dark interior of the cabinet, and I have no problem flowering.
On the inside, I clamped fabric shop vacuum bags over the ends of the PVC tubes, which protrude into the cabinet a bit for that purpose. The vacuum bags keep the "borg" out (mites), as well as stray pollen from unwanted male suitors growing outside in some neighbor's back yard [or clouds of hemp pollen from Canada! - ed].
Moving over to the first cabinet stack, the mother compartment is serviced the same way, but I only use one 3" opening. Airflow from the lower flowering cabinet next door is sufficient as an inlet in the upper flowering cabinet, but I did add one 3" inlet for use in summer, when some additional cool air is welcome.
I use 200 CFM Dayton squirrel cage fans both in the mother compartment and the upper flowering compartment. If we're designing a system with three flowering cabinets, I would use one in each. These fans are compact, easily mounted with integral tabs flat on a wall, and they are efficient and quiet. The big Dayton may be a bit of an overkill in the mother compartment, but it's easier on the mechanicals to use a large fan on now and then vs. a smaller fan huffing away all the time.
The fans have a square outlet tube that fits into nothing I am aware of; why do they do that? In any case, I stole the aluminum tube that comes with the dryer vents I use, flattened it out into a sheet and molded it into an adapter, converting the square hole of the fan outlet into a circular opening to insert inside a piece of flexible dryer outlet hose. I just used duct tape to strap the whole mess together. OK, it's not very sano, but it works.
What about CO2? There is little room for the mechanicals, the scrog blanket will already get as thick as it can be, and the fans are on quite a bit with the hot lights in the enclosed space, and would blow out the CO2 regularly (every five minutes or so). So, I doubt it would be useful in this limited growing situation.
The outlet is also a 3" PVC pipe punched through the wall. The inside protrudes into the cabinet as a place for the flexible dryer conduit to be clamped. The outside outlet is another dryer vent, with the flap pieces left in place to prevent insects and debris from floating in through the outlet tube. I ran the outlet right out through the eave line in the soffit, where it exhausts into some bushes.
What if you don't have the luxury of being able to tap the outside air so easily? Well, you can draw air from a crawl space if there is one below the cabinet, by running 3" PVC tubing up inside the cabinets to the desired compartment. If you use Rubbermaid 11 gallon containers mounted sideways, there will be enough space in back to run several such conduits. I ventilate the mother cabinet like that. The same holds true for the outgoing air. The fan can exhaust down a 3" PCV pipe into the crawl space, and flexible tubing can carry the air to the nearest available hidden outlet. You can't run air through tubes that are too long, or the fan won't be able to push the air needed. But I have tested a run of over 20' with no problems. I didn't use it, but the fan moved the air easily.
Controls
The fans need to be wired up to thermostats as controls, a humidistat too, if you can afford it. I use both, but I find the humidistat wasn't needed, as there is frequent enough airflow through the cabinets to avoid high humidity.
When selecting a thermostat, I recommend you avoid cheap units and get something decent. I use the industrial gray Dayton units with the exposed black coil. Damned expensive, but they work very well, keeping the temperature within a range of a few degrees from the setting. I used cheaper units at first, but the things allowed the temperature to fluctuate all over the place, and I ripped them out in disgust.
We want to mount the thermostats up high in the cabinet, where the buds will be growing, as that is the airspace that is critical. Generally a temperature of 70-75 degrees is recommended, and the combination of the Dayton 200 and the good thermostat nails it on the button. I sound like a commercial for Dayton products. Little do they know... [I bet they know perfectly well! - ed.]
All the lights and pumps are controlled by cheap hardware store dial timers, which I plug into wall sockets I built into the cabinet walls. These timers are junk, but have failed on me only once (costing me an entire mature Durban sea of green crop while on vacation, you bastards!). I have considered more expensive, and presumably reliable, timers, but haven't done so yet. Although the ballasts are by themselves in a separate compartment, they started off sharing the flowering cabinet space, and the outlets and timers are all still located there. That means I have to run some power cords from the timers through the walls into to the ballast cabinet, but it doesn't look too messy; there are already cords coming from the ballasts to the light hoods.
The reservoir cabinet has its own outlet and timer. I run the pumps for both reservoirs and the air pump from a single timer.
Water
The bottom compartments hold the reservoirs, and 11 gallon Rubbermaid storage containers work great. They will be in the dark, but it's not a bad idea to wrap them in black plastic to keep all light out, which prevents the growth of algae [also for the growing containers, of course - ed]. Cut out a window to check for water level of course. I use submerged Little Giant type pumps. The 8' compartment stack requires a pretty hefty pump, as there is quite a vertical distance for the water to climb. The pumps show how high they can push water on the side of the box. Again, go more robust than you need to provide a cushion.
1/2" drip system tubes work fine to deliver the water up into the cabinets, but you can also use hard-wired PVC plumbing bits and pieces, and there are adapters to mate the two. If you use PVC, go 3/4" to allow the water to mix with air on the drain leg. I used 1/2", but would go larger if I was starting over.
The water needs to get from the plant containers back down into the reservoirs, and gravity handles that. There are myriads of ways to plumb the system. I choose open drain holes cut into the floors of the compartments. I use Rubbermaid containers to grow in, and mount a cheap chrome sink drain in the bottom of the containers (more hole saws to buy). The chrome drain piece sits in the hole in the floor and drains into a large PVC adapter fitting that is plumbed into the drain system, all connected together and flowing back into the reservoir below.
For a long time I relied solely on the action of the water splashing down the drain tubes and into the reservoir to aerate the solution, and it works fine. But when I added the second flowering cabinet next door, with its own reservoir, I lost that effect due to the short distance the water falls. So recently I added a good quality aquarium air pump connected to an airstone in each reservoir.
Every couple of weeks the reservoirs need to be drained, and while you're plumbing away here, add a fitting to the cabinet to connect a hose, plumbed into the pump outlet line. That way you can connect the hose, turn on the pump and allow it to drain the tank to the outside. The hardware store is an endless source of valves and connectors to fulfill any elaborate design you like, to get water in and out of the reservoirs. I plumbed in valves in each compartment as well, so I can isolate one compartment from the water system during maintenance, etc.
Water is added to the reservoirs with a 1/2" drip tubing piece connected to a quick connect hose coupling. The drip tube piece pokes through a hole drilled in the container top (yes, another hole saw to buy). Filling up is clean and easy. Nutrient mixes are added from a jug with a piece of the same 1/2 drip tubing mated to the top. As I mentioned above, I plumbed in a valve and outlet in the line from the pumps in order to use the pumps to drain the reservoirs out through a hose for changing the water. I do so every two weeks.
Vacations present a special problem with such small reservoirs. To avoid having a friend or two watch over the grow (the less people who know, the better), I added a McMaster Carr brass float valve assembly to the Rubbermaid raised lid. That could be connected to a hose, but the consequences of an open hose leaking or a connection breaking gave me the shivers. Instead, I bought a 30 gallon storage container as a supplemental vacation reserve. I place it on a shop table and it gravity feeds the McMaster Carr float valves. If it blows up, I will only have 30 gallons leaking, not the contents of the entire Seattle water system. I don't normally use the float valves for water input, as they maintain the water level a bit below full, due to the clearances involved with the float.