Bierliebhaber

Recipes 

I would recommend waiting to dry hop until you return. Leaving the dry hops in there that long could lead to some vegetal flavors.

Also, if you're using pellets don't dry hop in your keg. Use a secondary or toss them in the primary when you get back. I personally prefer racking onto them in a secondary.

badbrew

Recipes 

Try using an air lock now.

seckert

Recipes 

if you want to use the airlock and are afraid of it drying out. instead of putting water in it put some cheap vodka. it will not evap and as an added benny if anything get in there for any reason the vodka kills it.

KevinW

Recipes 

Good advice so far, once the "active" phase of fermentation is done the airlock should have very little activity so leaving liquid (vodka, star san, water, etc..) will be fine. I have had (I use cheap Tequila) my airlock bubble for 3 weeks and the alcohol is still in it.
Come to think of it, I wonder if I am having a problem with my beer since I have never had a beer "off gas" for 3 weeks before. Oh well, time will tell!

One of the hardest things about brewing I have learned is patience! Time does tend to heal most wounds in brewing.

Good luck!

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“I don't drink beer all the time but I can drink (a) beer anytime" - Me