50% perlite is a little much for me. I'd make more for a better substrate that can hold some water and nutrients better.
Some light mix soil would be a great addition and it'll allow you to add enzymes and root stims and make for a good ground for bacteria, (which you can't do in coco) and light mix soil is more or less like a coco mix but you have to be careful as it tends to burn like soil if you feed to heavy in 1 sitting and by not following with water or water+enzyme feeds.
Happy growing and good luck on your 1st grow, you'll learn a lot.
Go light and steady and light def is better than a tox you can always add nutrients but once they given its very hard to take back.
Keep a close eye watch for the signs, brush up on leaf issues, difference between micro/Marco plant nutrients.