I need help controlling RH in Flower

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Odiesel

Odiesel

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Hey everyone i know the question is a super basic one but i cant seem to figure out how to get my RH under control at night. I am flowering in a 4x4 tent with a 6 inch ac infinity exhaust fan and I also have a 30 pint dehumidifier running nonstop in my room. I have my exhaust fan set to high at night with dehu going as well and i still see night time RH going up to high 60's. I am only in 3rd week of flower but have to get this under control before i get any further. At this point im considering purchasing a small dehu for the tent as well, but that seems kind of pointless since i can't imagine those puny little personal ones doing anything compared to the 30 pint one i have.
 
bigbagofbuds

bigbagofbuds

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Hey everyone i know the question is a super basic one but i cant seem to figure out how to get my RH under control at night. I am flowering in a 4x4 tent with a 6 inch ac infinity exhaust fan and I also have a 30 pint dehumidifier running nonstop in my room. I have my exhaust fan set to high at night with dehu going as well and i still see night time RH going up to high 60's. I am only in 3rd week of flower but have to get this under control before i get any further. At this point im considering purchasing a small dehu for the tent as well, but that seems kind of pointless since i can't imagine those puny little personal ones doing anything compared to the 30 pint one i have.

Don't waste your time and money with peltier based dehumidifiers (the small personal dehumidifiers), they will not work for our purposes.

If I had to guess I would say your dehumidifier is either too small or is old and no longer running efficiently, your best bet will be to upgrade to at least a 50 pint dehumidifier, oversizing the dehumidifer is better and doesn't have the issues that oversizing an air conditioner will.

Your RH is rising at lights off due to the temperature dropping, then your dehumidifier is not able to catch up. You can reduce the amount of humidity (no standing water etc...), reduce the temperature differential between lights on and lights off, and upgrade your dehumidifier to better control your RH.
 
CF89

CF89

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I got a little vivosun dehumidifier for in my 4x4 tent for week 4-10 of flower to help keep the humidity down. Did I waste my money?
 
Odiesel

Odiesel

426
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Don't waste your time and money with peltier based dehumidifiers (the small personal dehumidifiers), they will not work for our purposes.

If I had to guess I would say your dehumidifier is either too small or is old and no longer running efficiently, your best bet will be to upgrade to at least a 50 pint dehumidifier, oversizing the dehumidifer is better and doesn't have the issues that oversizing an air conditioner will.

Your RH is rising at lights off due to the temperature dropping, then your dehumidifier is not able to catch up. You can reduce the amount of humidity (no standing water etc...), reduce the temperature differential between lights on and lights off, and upgrade your dehumidifier to better control your RH.
It is a new dehu i just purchased last week so I might just need to exchange it for a larger one. I am also going to make sure not to water late.
Probably going to get some more fans in there for better circulation as well
 
Aqua Man

Aqua Man

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Slow the temp drop by controlling room temps. This will slow the rise in humidity and allow the dehuey to keep up.

If you can of course.
 
bigbagofbuds

bigbagofbuds

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I would return that Vivosun dehumidifier for 2 reasons.

1. Its capacity is less than 1 pint a day (400ml).
2. Dehumidifying within the tent will only work if you are not doing constant air exchange (sealed or partially sealed environment).

The main issue with dehumidifying from within the tent is that the air moves through the tent too quickly for the dehumidifier to work, as soon as the air is dehumidified its evacuated from the tent and so doesn't affect the tents RH as intended (assuming you are ventilating 24/7 and not in a sealed or semi sealed environment).

If possible I would return the 30 pint and upgrade to a 50 pint, otherwise consider buying a 50 pint and using the 30 pint as a backup for when things fail, because they will fail.
 
Aqua Man

Aqua Man

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I agree you need 30-50 pint the peltier are not only extremely inefficient but way to undersized. They are meant for like a clothes closet not transpiring plants that produce a lot of moisture. One more gimmick they put cheap just to sell and not do its job adequately.
 
CF89

CF89

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Man I really gotta stop buying that vivosun garbage.

their 6” inline fan is useless and apparently their dehumidifier is too.

cheap pays twice I guess. A lesson I learned 20 years ago and still don’t apply to my real life.
 
Aqua Man

Aqua Man

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It is a new dehu i just purchased last week so I might just need to exchange it for a larger one. I am also going to make sure not to water late.
Probably going to get some more fans in there for better circulation as well
Water in the early part of lights on. This is when the plants need it. Slow the temp drop or get a bigger dehuey.
 
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