What skills do you use on your Monk?
I'm at level 26 right now, about to beat Act 2. I've been playing with my friend who is a Sorceress. He basically puts out massive AoE damage so I've been doing single target stuff.
I really love when you get to level 30 and can have three passive skills. Good stuff.
Here's what I would use at 26:
Primary: Crippling Wave
Rune: Mangle
Secondary: Tempest Rush
Rune: Tailwind
Defensive: Blinding Flash
Rune: Self Reflection
Techniques: Dashing Strike
Rune: Flying Side Kick
Focus: Cyclone Strike
Rune: Implosion
Mantra: Mantra of Evasion
Rune: Hard Target
Passive Skill 1: Chant of Resonance (Fleet Footed is good for farming since you have lower spirit use)
Passive Skill 2: Seize the Initiative
This build is good for farming as well as tanking at your level. You basically use dashing strike to get to key targets, then cyclone strike to pull them in and then spam crippling wave. If you're in a group, you adjust these tactics for control for tanking purposes. The monk is about AOE damage and mob control - single target damage is poor. At lower levels the monk can farm faster than any other class (WD overtakes this at higher levels but the monk is still second best).
Edit: Also, like I mentioned before, the key to this build is Seize the Initiative. Stack dex above all else followed by vitality. Go for high armor pieces if possible as well as spirit regen and life on hit. Use a fast fist for main hand and offhand a shield with high armor and high dex, no dual wield. With this build and proper gearing at 26 your hp should remain at max the whole time and you'll have good mob control.