Mother Earth 70/30 Coco/Perlite start to finish I never add anything else other than water and nutrients. Honestly I've grown in both coco and coco/perlite and can say the perlite is a crutch but it does help in my experience with determining if I've watered enough when hand watering.
Some say whatever % Perlite you add is the percentage of your pots capacity you're removing since roots can't grow through perlite rocks, so a 10 gal is really a 7 gal if you were to be running 70/30 coco/perlite vs 100% coco. I think this theory actually holds true because I'm able to water my 10 gallon coco pots every day with 2 gallons of feed at their size.
Anyways, really all you need is pure coco but the perlite will help with drainage and I personally think the roots like it better. It's kinda a buffer ya know?
p.s if you're hand watering, you shouldn't need to add anything to the bottom of your pots. I'm imagining the bottom drying out faster than the top isn't good.
