[Brilliant Diamond & Shining Pearl] lower affection

So I was told that to lower affection is to go to Eterna City and buy revival herbs and energy roots. How much do you have to use? I gave each pokemon a energy root after getting damaged. But some are still holding on so i wont feel bad. I really dont like my pokemon being invincible.

Maximum Friendship value: 255. Sees benefits at 200 Friendship and up.

Deducts 10 points per Energy Powder, Heal Powder, Energy Root, or Revival Herb when at 200+ Friendship. So, at least 6 total for each Pokemon. (Note: Loses only 5 points per at Friendship values below 200.)

Gains 2 points per level gained (not through Rare Candies). May wish to use more than you need to stay good for a while. (Serebii link to all Friendship changes: here.)

Checks their current Friendship value in two different ways.

1. Go to Eterna City's Pokemon Center. Look for an Aroma Lady. Gives you the Affection Checker Poketch app. Touch and hold a Pokemon on the app.

2 large hearts: 255 Friendship
2 small hearts: 200-254 Friendship
1 small heart: 150-199 Friendship
No hearts (moves towards touched spot): 70-149 Friendship
No hearts (moves away from touched spot): 0-69 Friendship

2. Go to the Pokemon Fan Club in Hearthome City.

0-49: Hmm... It seems to dislike you a little.
50-89: It's feeling neutral toward you. It's up to you to change that.
100-149: It's warming up to you. That's my impression.
150-199: It's quite friendly to you. It must be happy being with you.
200-254: It's very friendly toward you. I can tell you treat it kindly.
255: It simply adores you! Why, I feel like I'm intruding!

Its worth noting as well that since Friendship and Affection were merged, if you lower it too much you won't be able to make any evolutions that depend on Friendship i.e. Eevee into Espeon / Umbreon, or Buneary into Lopunny.