Properly planning out your grow is by far the most important step aside from acquiring viable seeds. If the tent is too small or too large for the growing accessories it's not going to be a good fit. Similarly you need to determine if the room you are using to grow can support the tent.
Below is a 48"x48"x80" grow tent. It has a 600 watt air cooled light with digital digital ballast, with air filter and 440 CFM fan. CFM is short for cubic feet per minute (cu ft/min). It is a measurement of the velocity at which air flows into or out of a space. Both the fan and the light have dimmers which allow the operator to change the strength (50% - 100%).
This is particularly desirable for the fan, as they can be rather loud when at full strength.
How to determine the right CFM fan for your room
Multiple the Length x Width x Height of your grow room or tent. This will give you the cubic feet. Most grow shops suggest a fan that can pull this much cubic feet in 1-3 minutes.
Personally we went with a stronger model, because we did not know how much resistance the activated charcoal filter and bends in the ducting would add to the fan.
The filter and the fan are fixed at the top of the tent. This was to prevent any spacing issues as the light hood is raised. The fan pulls the air through the light hood and prevents it from becoming too hot. This means as the plants grow taller the light hood will still have room to move up towards the top of the tent without being a heat hazard.
We chose this option because the noise is greatly reduced with the fan inside the tent. However if it isn't noisy or bothersome, having the fan outside the tent means less heat being generated inside.
More importantly having the fan close to the filter will increase efficiency. The cool air will be pulled in from below your plants and up and out through the top of the tent. Isolating the majority of the heat to the top of the tent.
The fan was securely tied to the top of the tent with string rather than fixed to a wall. This was done to reduce noise from vibrations. The fan when on lowest setting sounds like white noise.
The hot air that is removed from the tent needs to go somewhere. In our case the nearest window of the house was the easiest option. We aren't sure that this is the best solution, so we created a simple window vent. This fan is strong enough to be combined with a second tent. When we purchased it, that wasn't something we were considering but it will save on a second fan. Buying larger is not always best, but in this case it worked out.
NEVER VENT INTO YOUR ATTIC
Moisture will leave the grow tent / grow room through the vents. If you vent into the attic or similar space, there is a risk of mold. Venting outside through a air filter system is a good way to avoid this issue altogether.
Since this is not a permanent fixture. We went with a foam sealant. This was selected because it is reliable and inexpensive. There are also many products that safely and effectively remove it.
Major takeaways
- Plan out everything you do before you do it. Even if you do this, it is still possible you're going to realize later there is a better to do it. We end up trekking back to the hardware store a lot because our initial plan ended up not being perfect. But at least we had that for a baseline.
- Research all products you are considering buying. The customer reviews are a great indicator of product quality and also best practice. If you don't find a lot of people doing something a certain way, there is probably a reason not to try it.
- Make sure you're buying the right sizes for the space you have to grow in. You don't want to get lights/fan systems that are too weak or too strong.
- Most importantly - Have fun but do your homework. There is a lot of online material and friendly forum support for indoor cultivation.
- Less fun Disclaimer: Obey all laws when cultivating marijuana in your area. Do not put yourself or others at risk for harm, and take all precautions when DIYing.
MM's
