Not sure if this might end up sounding like a noob question but I'm just starting to properly IV breed in the 6th generation. Basically I'm wondering if it's possible to breed a true flawless 6 max IV Pokemon. I know the destiny knot carries 5 between the two breeders but I'm wondering if there's a way to get the full 6.

I'm breeding Shellders currently, these are the parents and their max IVs:

Male: HP, Def, Sp.Atk
Female: HP, Atk, Sp.Atk, Sp.Def, Speed

Is there any way I can get a full max 6 IVs on one of them (I'm going for mixed attacker) without sacrificing the nature i.e. removing the everstone?

Google didn't help much, but thanks if you can help.