Articles to be used on website and for SEO (medical niche)

HI, I need some articles to be used on my website and some for SEO purposes. Requirements: - No grammar and spelling errors - Articles must be unique and quality - Need to have clear understanding for SEO writing after the penguin update - Include "fish" in your bid so i know you read the description - I will provide keywords to be used and keyword density - Budget is $30 for this batch so please include in your bid how much articles you can write for $30 - If I'm satisfied there is more work to come Good luck!