Any help EV Training a Marill?

Question

I was EV training a Aarill and I defeated 20 Patrats and when I leveled up it said +0 in its attack. Am I doing something wrong?
Something to add, it's currently on level 10 but it was on level 9 at the time when it was being EV trained.

Comments

Marill's attack stat is not the highest; it will not win much attack through EV training and level up.
Azumarill will not show you a huge difference; if your ability is Huge Power and you have Adamant nature, you're doing it right.
It's mainly when reaching level 100 that you really feel the difference between EV training and lack of it.
Don't worry, you're not doing anything wrong. (Hint: Use Power items. They add on your EV training and speed it up.)

Answer 1

According to how the stat formula works, this is possible for certain Attack IVs if your Marill has a nature that lowers Attack. If your Marill's nature does not lower Attack, then you must have done something wrong, because with the information you've given, its Attack should rise by at least 1 when it levels up to level 10. (I wrote a program that checked the outcomes for every possible IV, so this should be accurate.)

Off the top of my head, make sure your Marill is actually defeating the Patrat, or at least participating in the battle - the Exp. Share in the sixth-generation games doesn't share effort points, only level experience. (EDIT: No, apparently I was remembering this wrong, sorry.)

Comments

Thanks and by the way it has adamant nature and the huge power ability. I think I will research EV training a bit more.