I know you said this is passive income but without an amount of hours spent it's really hard to judge if you're profitable of not. How many hours a month are spending? How much of this is going to taxes? Is this on-top of your full-time job?
I also think it would be worth moving to a site like medium or redesigning your current site.
About 80 hours of month spent on maintain website, Flippa and various other things. I only started this on the early part of this year, so I can't explain the tax side of things yet, but if you make over $600 on products or services, then you must report it to the IRS here in the USA, which I will do of course. All of this is still a learning experience for me, so by this time next year, I will be able to explain things in a better way.