HOW TO VENTILATE YOUR GROW TENT?
To ensure that the air in your grow tent is the same throughout, the intake and exhaust ports should be opposite each other, and the air between them should be mixed (see Fig 1-2-3). In large tents that are long, two exhausts and two intakes can be used.
WHAT ARE THE FLOW RATES FOR THE EXTRACTORS AND FILTERS?
The capacities in m3/h (cfm) indicated on the extractors are measured without filter and without external stress (in the open air). A filter with a capacity at least equal to that of the extractor must be used. The use of a filter reduces the flow rate of the extractor by 30%, up to 50% when it is old. Using a passive “DUCTING FLANGE – LIGHT BAFFLE” intake on a Secret Jardin grow tent will reduce the flow rate by 40%. Example for a DS120 120cmx120cm: 350m3/h without a filter, for a flow rate of 275m3/h with a filter and 160m3/h in the tent with a filter and a light baffle : The air is changed every 1-2 minutes, depending on the condition of the filter (160m3/h / 60 min / 2. 9m3 = 0.9 times per minute).
HOW OFTEN SHOULD WE USE EXTRACTION?
We propose three levels of ventilation. “The air in the tent is renewed every ? ”
– 1 to 2 min: Growing and intensive cultivation, with temperature problems (outside air > 25°C or lighting too hot, like open HPS).
– 2 to 4 min: Growth and intensive growth, without temperature problems
– 4 to 8 min: Propagation, seedling, light growth, vegetation, no temperature problems.
Extraction should only be used to allow the plants to breathe. We design our products so that you don’t need to “over-ventilate” them, if the incoming air is between 15°C and 25°C and if your lighting system is cold (e.g., LED or ventilated HPS).
WHEN IT’S TOO HOT?
Sometimes the outside temperature is too high. The graph opposite (Fig 4), which applies to configurations below 5m3, will help you anticipate these situations. Here are some ideas:
– Cool the incoming air or connect a duct to a cooler location.
– Use plant lighting at night when the outside temperature is coolest.
– Also remove the flow-limiting filter, if possible.
– Replace the light baffle with a conduit long enough to keep light out.
– Add one or more “passive intakes” by adding a DOUBLING FLANGE and a LIGHT BAFFLE.
– Add an “extractor” that blows air into your tent.
SPACE BOOSTER OR INTRACTION?
For the outer shell to hold the frame in place, there must be negative air pressure in the grow tent. This also prevents odors from being emitted, thanks to the addition of a filter. The larger the tent, the more this negative air pressure encroaches on your grow space, in some cases even causing your tent to implode. If the grow tent is too large, you need to add suction, which should not exceed 70% of the extraction to maintain negative air pressure inside the tent. Without the Space Booster, which comes with our pre-equipped grow tents, you will need to add this intake from the 120×120cmor 100×100cm tents. With the SPACE BOOSTER, you need to add an air intake with tents from 150×150cm, or even more if you change the air infrequently, as is the case during propagation.