Low Humidity

My 5x5 is keeping a consistent 30% relative humidity at ~75-77ºF.
Is this too low? What's the worst that can happen when the humidity is that low.

Put cups or jugs of water in the growspace under the lights

You want your Humidity to be at that range. Good for flowering, don't know if its one of them myths but Ive heard it produces more females. If you want to raise your Humd, fill up a bucket and place a towel in it with 1/3 of the towel out of the water. My humd never goes above 30. No probs whatsoever

I have a 4x4 and had the same problem. Water in a container doesn't work well if you have high air circulation like i do, maybe its because its negative air pressure too, idk. Soaking wet towels work real well, but dry out in a few hours so that doesn't work. My veg was low so i bought a $40 humidifier and that worked fine. I bought one for my flower room too and it worked but i had to crank it all the way up to get just over 40% humidity with all that air circulation. It was a bitch to fill the thing 2-3 times a day. So my veg plants matured and I went from having 3 plants inside the tent to 10 plants. Now everything is covered, have the same air circ, and humidity is at a constant 45% which is awesome. It's amazing how much moisture the plants can hold and even respirate back into the air. Everything is soft, cool, and healthy. So really the best suggestion is add more plants lol, but this isn't a great solution. I'd say either humidifier, or add plants, humidifier being the more reasonable but less efficient option.

Will I see a loss of yield due to low humidity?

If not, I'd sooner just leave it since it should prevent some mildew

I keep mine at 30% never higher than 40% in flower and in veg its 50+%

I grow once a year, usually early Sept. to Dec. Then, living in the north, humidity isn't much of a problem. 30%-40%. This year I had to wait until mid January. Very dry, most of the veg time was too low to register with my hydro device. I've used the bucket-towel trick in the past without much, I've felt, effect. This time I said fuck it. It is what it is. I think my yield is going to suffer, but with five females under 400w, I'll harvest enough. Four weeks into 12-12 they're frosting up nicely.

I Dont listen to em about 50%+ humidity.
Indicas come from areas that look like Death valley.
I seen NO difference when I started running 20-30 % humidity.

Low humidity mean less chance of mold, an more resin production in flower acording to aurthor Robert Clarks advanced marijusajuana Botany.

http://www.mellowgold.com/grow/mjbotany-removed/

Yeah low rH supposedly increases resin production. I ran 30% rH flower and it turned out great.

X

I keep mine at 40-45 in flower, 60 in veg.

Mine is 30-40% and my plants love it.

It's so dry where I am that it doesnt even register except lights off in flower, and thats still real low. Dont know if they suffer but they were frosty as hell

to actually answer your question "what's the worse that can happen?"

lower yields, slower growth, irregular water schedule

will it kill your plants, NO will they be ok, YES

wanna truely understand why it matters? read this
http://www.arguscontrols.com/articles/VPD_Application_Note.pdf

wanna raise the humidity in your tent? put a humidifier in the room the tent is in and adjust it where you want it, make the air that is being sucked into your tent the proper humidity

Ah yes,... the awesomeness of VPD ...zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz

J/K...

Hm,.. I guess I'll keep it simple and decrease chances of mildew. If I lose 1-2% yield, I suppose that's acceptable collateral damage in the war against PM.

low humidity will cause your plants to drink alot more and I find I have to watch the ppm more
cus it tend to rise with a lower RH

I'm watering every three days with 3gal pots.