HOW TO VENTILATE YOUR GROW TENT PROPERLY?
To homogenize the air in your tent, the inlets and outlets must be diametrically opposed, and the air in between must circulate through each other (see Fig 1-2-3). For large, long tents you can use two extractors and two supplies.
FLOW RATE OF THE EXTRACTORS AND FILTERS?
The capacities, in m3/h, stated on the extractors are measured without a filter and without external obstacles (ie in the open air). A filter with a capacity at least equal to that of the extractor must be used. A filter will reduce the flow rate of an extractor by 30%, and up to 50% after use. A passive supply of the type « DUCTING FLANGE - LIGHT BAFFLE », in a Secret Jardin tent, will reduce the flow by 40%. For example in a DS120 120x120 cm: 350 m3/h without filter gives 275 m3/h with filter and 160 m3/h in the tent with filter & light damper: The air is then refreshed every 1 to 2 minutes, depending on the condition of the filter (160 m3/h / 60 min / 2.9 m3/h = 0.9 times per min).
. WHICH EXTRACT FREQUENCY TO CHOOSE?
We propose three ventilation levels. « The air in the tent is changed every ? » • 1 to 2 min : Growth & Intensive growth, with temperature problem (Outdoor air > 25°C or Lighting too warm, open HPS type)
• 2 to 4 min : Growth & Intensive growth, without temperature problems
• 4 to 8 min : Propagation, seed, light growth, vegetative growth, no temperature problems
It is ideal to use the extraction only to allow the plants to breathe. We develop our products in such a way that you do not have to "overventilate" them, if the incoming air fluctuates between 15 and 25°C and if your lighting system is not too hot (e.g. ventilated LED or HPS).
WHAT TO DO WHEN TEMPERATURES TOO HIGH?
In certain situations, the outside temperature becomes too high. The adjacent graph (Fig 4), which applies to installations of less than 5 m3, allows you to foresee these situations in advance. Here are some ideas :
• Cool the incoming air or connect a duct to a cooler place.
• Illuminate the plants at night, when it is least warm.
• Remove your flow-restricting filter if possible.
• Replace your light muffler with one long enough to block out the light.
• Add one or more "passive feeds" using a DUCTING FLANGE and a LIGHT BAFFLE
• Add an « extractor » that blows air into your tent
SPACE BOOSTER OR SUPPLY?
The envelope can only properly hold the structure if the tent is airtight. This also prevents the spread of odors by adding a filter. The bigger the tent, the more this negative pressure will affect your grow room, which in some cases can even cause the tent to collapse. For tents that are too big, add a supply, which should not exceed 70% of the exhaust, to keep the tent under negative pressure. Without the Space-Booster, which is included in the tents with included accessories, you must add this supply of 120x120 cm or 100x100 cm. With the SPACE BOOSTER you only need to add this supply from 150x150 cm, when you will not change the air often, such as for the propagation.