Normally, first berry lowers to 100, second is -10 (to 90), third is -10 (to 80), etc. The only limit of berry unusability is when there are both 0 EVs left in the stat and the Pokemon is at max happiness. If one condition is satisfied, but not the other, the game will inform you "X stat can't go any lower" or "it adores you" or something.
Not sure why on your problem, as you describe it, unless you EVed other stats before the attack and accidentally made it so only raised it to 100 or less EVs.
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"So if lets say my Rhyperior has 252 Atk, I use one Kelspy Berry it lowers to 100. Then I use another 9 Kelspy berries it should lower to 10."
http://www.smogon.com/forums/showthread.php?t=39554
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Every time it gets over 100, it will lower it to 100 on the first berry, no matter how many times you bring it over then down.
Not sure why on your problem, as you describe it, unless you EVed other stats before the attack and accidentally made it so only raised it to 100 or less EVs.
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First lowers TO 100, not BY 100.I see, I thought all of the EV deleting berries lowered the EVs by ten, not that the first lowered it to 100 and then any additional ones do it by ten.
The pokemon who's EVs I'm trying to redistribute all have their 510 and are at max happiness, if I'm understand what you're saying I should be able to use the berries if the pokemon have either EVs to delete in a paricular stat or aren't at max happiness.
If a pokemon is at max happiness and has no EVs to delete, the berries won't work.
So if lets say my Rhyperior has 252 Atk, I use one Kelspy Berry it lowers to 152? Then I use another 9 Kelspy berries it should lower to 62?
Also I assure you, the EVs for my Rhyperior are 200 Hp, 252 Atk, 58 Def. I also used the other berries to check if there are EVs in the other stats but the berries said they "would have no effect" so there aren't any EVs in SpD, Sp Atk, and Speed.
"So if lets say my Rhyperior has 252 Atk, I use one Kelspy Berry it lowers to 100. Then I use another 9 Kelspy berries it should lower to 10."
http://www.smogon.com/forums/showthread.php?t=39554
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Every time it gets over 100, it will lower it to 100 on the first berry, no matter how many times you bring it over then down.