There's probably millions of them in my tank litearlly, they're really small, and they flex their bodies front and back and float around my tank, they also crawl and glass and on my black sand, and also driftwood, hell I've even seen them crawling on my snakeheads, they're everywhere. They've been there for over a month now, I do weekly 30% waterchanges and lessened feedings and I still see no reduction in their numbers. They also attach to my glass and their heads look like it comes to a tri-forked end. I believe it's planaria, and putting in guppies to combat them is not an option, as i said I have snakeheads in my tank. Any useful advice guys?