Would AC help bud rot ? ( 30c temp , 80% humidity)

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Hi guys. I have but rot :((( I have left like 2 weeks tops to end , but now I’m cutting one branche like every day as it gets rot . Plants never pruned or anything so very leafy. That’s why humidity so high. I have Intake but humidity in my house is 70% as-well :((
would a small AC in tent kill some humidity ?
 
Short answer: Probably not in this situation - you may just end up increasing the relative humidity inside the tent.

AC units provide some dehumidification to air as the air flows over their cooling coils, but cooler air also holds less water. For example, if you cool 30°C (86°F) / 80% RH air down to 27°C (81°F) without removing any water, the RH would increase to 100%. I'm not sure the dehumidification provided by a small AC unit inside the tent would offset that....I'd have to re-learn my HVAC psychrometric charts.

Theoretically, if you have the exhaust of that AC unit venting inside the tent, then technically it should have no net cooling effect (and perhaps, even a net heating effect due to inefficiencies) while providing some dehumidification. I.e., it should act just like a regular dehumidifier (but perhaps less efficient). However, some / most portable AC units are designed to mix in the condensed water with the exhaust instead of collecting it in a tank, which would defeat the purpose here.

You may be better off running your home AC full blast and/or opening windows (if outside RH is lower than inside) to lower your house RH. Otherwise, a medium / large dehumidifier in the lung room would be your preferred solution. Realize that all the water you're adding to your plants is being released into the air and has to be removed somehow. You could try defoliating somewhat to reduce water usage, but that could be playing with fire.

If you already have dehumidifiers running and they're just not keeping up, you could try desiccants as a last-ditch effort...but I can't guarantee it'd work, it's only a short term solution, and it's not cost-effective long-term vs. getting an extra dehumidifier. Desiccants are what are used for rapid-dehumidification in the more expensive commercial dehumidifiers (e.g., for quickly drying out a flooded home). Calcium chloride can absorb up to 3x its weight in water and is sold as rock salt / road & sidewalk de-icer at home improvement stores for ~$20 / 50lbs. You could DIY something on your intake to have the incoming air pass through the rock salt (e.g., in a 5-gal bucket), but that would reduce your overall air flow, could end up blocking the air flow, etc. I'd put that in the "science experiment" category for now.
 
Short answer: Probably not in this situation - you may just end up increasing the relative humidity inside the tent.

AC units provide some dehumidification to air as the air flows over their cooling coils, but cooler air also holds less water. For example, if you cool 30°C (86°F) / 80% RH air down to 27°C (81°F) without removing any water, the RH would increase to 100%. I'm not sure the dehumidification provided by a small AC unit inside the tent would offset that....I'd have to re-learn my HVAC psychrometric charts.

Theoretically, if you have the exhaust of that AC unit venting inside the tent, then technically it should have no net cooling effect (and perhaps, even a net heating effect due to inefficiencies) while providing some dehumidification. I.e., it should act just like a regular dehumidifier (but perhaps less efficient). However, some / most portable AC units are designed to mix in the condensed water with the exhaust instead of collecting it in a tank, which would defeat the purpose here.

You may be better off running your home AC full blast and/or opening windows (if outside RH is lower than inside) to lower your house RH. Otherwise, a medium / large dehumidifier in the lung room would be your preferred solution. Realize that all the water you're adding to your plants is being released into the air and has to be removed somehow. You could try defoliating somewhat to reduce water usage, but that could be playing with fire.

If you already have dehumidifiers running and they're just not keeping up, you could try desiccants as a last-ditch effort...but I can't guarantee it'd work, it's only a short term solution, and it's not cost-effective long-term vs. getting an extra dehumidifier. Desiccants are what are used for rapid-dehumidification in the more expensive commercial dehumidifiers (e.g., for quickly drying out a flooded home). Calcium chloride can absorb up to 3x its weight in water and is sold as rock salt / road & sidewalk de-icer at home improvement stores for ~$20 / 50lbs. You could DIY something on your intake to have the incoming air pass through the rock salt (e.g., in a 5-gal bucket), but that would reduce your overall air flow, could end up blocking the air flow, etc. I'd put that in the "science experiment" category for now.
Thank you so much for taking your time for such a lovely answer. What would you recommend if I will allow myself to spend some money on Desiccants . Even for shot term as I would be done with my babies in 2 weeks. What would you recommend? ( let’s say from amazon )
 
Frankly, I would not recommend desiccants unless you're a curious do-it-yourself type with no need for them to actually work.

Typical home or closet "moisture absorber" products (like this or this) are basically just calcium chloride sitting in a bucket. They don't work for grow tents because they're meant for small enclosed areas with stagnant air (i.e., slow absorption over time) and no air exchange (i.e., no outside air bringing new moisture in).

Getting those (or bulk calcium chloride) to work for a grow tent would involve a bit of DIY effort/trial-and-error to increase the airflow around or through the media in a safe manner. It's generally non-toxic, but can irritate skin, corrode metals, and be harmful to plants in large amounts - so, you wouldn't want small particles blowing around the tent. It also absorbs so much moisture that it can dissolve itself, so you need to consider liquid containment. Bulk road salt would consist of larger crystals - which could be fine to just dump into a 5-gal bucket in the path of your circulating fans - but you'd get better performance if the air went through or around the entire bed vs. just across the top.

Bulk silica beads (like this) would be easier to work with - they're inert and re-usable and don't drip - but are more expensive and hold a lot less moisture (~30% weight for silica vs. ~300% weight for calcium chloride). You could put them in cotton or silk bags (like this or this) and either hang in the tent near your circulating fans, or pack them into a section of round flexible aluminum ducting on your tent intake.

How quickly either one would be used up and how much you would need depends on your number of plants, how much water they use per day, and your overall ventilation air flow rate through the tent. For comparison, 5 lbs of silica (~$20 - $35) holds about 1L of water before needing to be recharged by drying in an oven. 50 lbs of calcium chloride (~$10 - $20) holds about 70L before needing to be disposed.

Overall, it's basically either "spend a lot of money on a lot of expensive silica so you're not recharging all the time" or "spend a lot of effort (and possibly extra time and money on hardware and trial-and-error) trying to DIY cheap calcium chloride to work well".

Either approach can quickly reach the level of "I should've just spent $200 - $300 on a big-ass dehumidifier..."
 
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