this is in Alpha Sapphire... i'm actually finding that chaining them with the DexNav gives you a good chance of getting parents with at least 3 31s, so I'm doing that... i've chained about 160 so far
Serebii.net Games - Individual Value Calculator i use this to calculate their IVs. normally theyre at level 1 or another low level, so you have to take them into the level 50 battles at the battle institute in mauville city