Don't know the vitalink soil and you didn't post what stage you're at in the grow. Some strains can't handle too much, particularly early on. I'm in a grow with 2 strains, have never grown either strain so I don't have any history, in a custom soil mix which has high nutes (use 45% PRO-Mix, 50% triple mix, add sheep manure at about 5%). Started low feedings (Advanced Nutrients Sensi Grow A&B) at 250 ppm at 8 days, both strains handled that well into the first feeding after transplanting them at about 3 weeks. As soon as I bumped the feedings to 375 ppm at around week 4, one strain handled it well and took off, the other (indica) showed ever so slight burn on a couple of leaf tips. And that's at 375 ppm!
My advice, if you're growing in soil, which has nutes in it as-is. Forget manufacturer recommendations, use ppm's as your measure, start very low (like 250 ppm), adjust up in low increments, watch the plants response before going up to the next level. Flush or at least water them a couple of times if they start showing nuts burn, then start back at the level they were happy. Once you now the strain and have run it, record what they liked and how they handled feedings for future reference.
Using manufacturer's recommendations, even 1/2 strength, you'll chance burning them. They're recommendations are of course self-serving and do not account for differences in strains etc. ppm's are ppm's and you can easily manage them/adjust as needed.
Cheers
