Humidity indoors

[Burton]

I am interested to hear from people with indoor systems.

 

My parental figures who think I will always be their "baby" were worried about my AP project because some far off acquaintance of the family destroyed their house with something "similar." My first though was, I am not a pot head so I am not that stupid, as this individual most likely was in my book.

Anyway they claimed they had to redo all the drywall because of mold and replace the ducting ...

 

Now I already thought about getting a dehumidifier anyway but really wanted to hear from others with indoor systems to see just how big of a problem it is for you and what you are doing to combat it.

 

My system will use a 300gal tank with LED lights and the HID's will only be on 4 hours a day (should be a huge factor in having less humidity via evaporation)

 

Thoughts?

[TCLynx]

Get the dehumidifier, get a big one and hook it up so that it can drain somehow so you don't have to remember to empty the bucket for it to work.  This will be noisy and will increase the energy used and also the heat in the room you situate it in but you don't want mold problems.

 

In some climates having fish tanks or hydroponics indoors isn't a big deal because they run humidifiers in their houses but in the southeast, much of the year it is humid.  To avoid mold problems you want to keep the humidity in the house below 50% Relative Humidity.  Get some of those thermometer that also tell the relative humidity and place them around so you can make sure.  Long before the drywall needs to be replaced, many people will experience allergy or sinus problems due to mold.  I'm in Florida and have experience with humidity problems though more climate and construction related than anything to do with hydroponics or aquaponics.

 

One more note, if your "fish room" is in the basement or somewhere that might not have very good insulation, this could actually cause condensation problems on the poorly insulated walls or whatever and those surfaces might experience mold issues even if you manage to keep the Relative humidity in the room rather low.  See warm air in the room can hold more moisture but if you have a cold wall due to the lack of insulation, as the warm moist air hits the colder wall, water will condense out of the air onto the surface and those places are where mold will start first.  The ground (dirt/earth) doesn't actually make good insulation.  It is a great thermal mass but it would only count as insulation if you are keeping the room in question at the same temperature as your local ground temperature.  If the basement is not being kept at the same temperature as the ground, and uninsulated wall with earth on the other side is going to have moisture problems from condensation.

(most of this info I've gotten from research into earth sheltered construction and the problems that often accompany such when people mistakenly assume that earth makes a great insulator.)

[Burton]

Yeah I am familiar with the condensation as I researched it before building my watercooling system for my computer years ago.

 

The room in question is on my first floor, I don't have a basement, it is well insulated the walls are never cold / warm ... There are two windows right near the grow area with the door about 7' away from the FT ... But there are heavy drapes on both of these made to block light.

 

There is a HVAC intake about 10' away and two HVAC outputs on the ceiling above both windows

 

Should I place the Dehumidifier next to the FT or place it near my HVAC (there is extra space next to it, I would not be connecting it to the HVAC directly) I guess I could put it near the window (next to FT) and feed a tube outside some how.

Let me get a picture for ya so you can see what I am talking about :D

 

Also I should mention we have wild humidity here, 0 to 100% year round >./p>

 

[TCLynx]

Sounds like you have already done some research.  Yea, I know about wild humidity.

[AJ Grottke]

Hey, indoor growing normally requires a dehumidifier.   That or at least constant venting creating negative pressure within the grow room.  During nice weather if u open up all the windows you might be ok with just that.

you said "My system will use a 300gal tank with LED lights and the HID's will only be on 4 hours a day (should be a huge factor in having less humidity via evaporation)".   Im not sure about that one.  Ive noticed when my HID's are not on there is much more humidity.  HID's produce alot of dry heat.  If you have a humidity meter in a room with nothing in it and it says %60 ; when u pop on a HID it will go down to at least 50% but more like 40 or 30%.  HID's decrease the humidity. Its not enough to offset transpiration, but it does help some.  When my lights go off I always get like 20-30% increase in RH due to night-time plant processes and no drying effect from the HID.

 

Are you growing in a sealed grow room, or just in your house?  This will make a big difference in how you should deal with humidity.

[Burton]

Its not going to be sealed. at worst I will create shoji screens to go around the grow area leaving room for air to flow in and out of the environment

[AJ Grottke]

You should just put a dehumidifier in the house.  Spot check all rooms and areas of the house with a hygrometer.  Find the areas that become the most humid, and put the dehumidifier there.   Putting it by the HVAC will do something but i think it would be better if it was places near the most humid areas and close to the growing areas.   I was gonna go into a long speel on sealed environments and their advantages, so im glad i asked that question.

[Burton]

Well obviously its nice to have it sealed so you can moderate environmental variables easier but to start off I think it will not be sealed. Eventually, if I see I am not getting the returns I want from the system I might seal it up and use those two windows more :)

But then I would have to purchase more equipment, like poly, fans, filter, CO2 monitors, oh my >.<

[Burton]

Wonder if we need to make a "Growing indoors" group so we can dump a lot of content into it ...

[Burton]

This is on the FIRST floor ... and yes IBC will fit just fine when they are cut in half through a door ... they are the GB's the FT is the 300g stock tank below them.

 

Also I think a IBC would fit through a door if you took it out of a cage as it is flexible :)

 

And this is my place lol no folks living here ... Dinning room isn't even in use outside watching TV occasionally, which I plant to move upstairs to my master bedroom as not to disturb the fish too much.

[jrtroubleshooter]

dehumidifier is going to use the electical saving of your LED, I had major humity problem with my system when I first started, I was able to mount small 8 inch in line duct fan that I got at home depot for $30  high above my garden no more issues.  try small fan first then work up in size, and equipmet, looks like you have window and outlet at simlar location as I, another option that I was considering if fan alone did not work was to partition off part

[TCLynx]

You might also be able to place the dehumidifier such that it could drain out the window next to the AP system.  Here in FL it gets so humid that fans just don't cut it (if you exhaust air, then other air has to come in to replace it and if the humidity outdoors is really high, it will not improve the situation so deciding what method to use will depend on local conditions at different times of year.)  A heat recovery ventilator might be a good choice certain times of the year and the exhaust fan might be the best when conditions are perfect but with the SouthEastern humidity, you will need the dehumidifier certain times of year.

[Burton]

TC is absolutely right a fan would never cut it most of the year here, especially being so close to the water. Then tack on the 90% humidity days when its 90 degrees out, or worse 110, and you are praying your power doesn't blackout lol

 

Ok so lets see ... new list of stuff I would need to buy.

 

Panda poly: max of 518sqft needed of black poly to seal it all in before seam allowance ... so a 10' x 100' roll ($70) would probably be good ... maybe I should get some black canvas and make it look smexy like professional grow tents (which cost a fortune and don't come in the size I need)

 

Air exchange: If set up right I assume this could work on one vent fan and axillary "circulation" fans blowing in the enclosure. idk about cost yet probably a DIY solution :)

 

Dehumidifier: how many lt/day? 70 is max (18.5 gal / day) and this could be vented out the window or collected and put back in the system as I have seen turtle / fish keepers do on other forms with success. (tested first of course) seems overkill for a 8'x11'x9' area.

 

Support frame: If I don't build the tent flush with the ceiling I could use hooks and hanging it from there I suppose ... but a support structure would probably make more sense ... The tent at max size would weigh at least 15lbs ... 1" or 3/4" pvc frame maybe?


A lot of potential design planning needs to be done now to see just what this would entail for me as I would have to put vents in the right spots so my in-wall heater and HVAC each have access to the space ... hmm ... if I am going to close it off though I would imagine it would be best to have it control its own temp and add extra flaps for the above just in case they are needed...

 

I am going to have to put the IBC's closer to the ground ... idk what I was thinking when I put them over the stock tank 0_0
while I wouldn't have minded building a platform to even reach to full GB it would only leave me 4' of grow room lol

I am going to play around with layouts, again, do you think I should keep the FT in the same confined space as plants, meaning both inside the same poly tent?