How much perlite to throw in black gold?

So I've read black gold natural and organic, is made with 25% perlite already, should I throw in an extra 15 or 20%?

Yes. You can kind of tell when you have the right mix as you go, but generally 50% total perlite is not unheard of for fast cannabis root development and drainage. Good luck

Squeeze the soil in your fist
It should make a form a clump that holds when you open your hand.

But the clump should break up if you poke it with your finger.

Something like that should be close enough.

Hell it may pass the test straight out of the bag though.
To be honest i don't really add to black gold because I use it on seedlings for a very short time.

Your probably better off to do it right.
Sometimes im lazy

as much as you want. the more you add the more often you will water, the more food you will have to supply