Yeppers that's the stuff, I buy the compressed brick of it that comes in a pack of three. I find you get more this way then the loose stuff. One brick fills a 10 gallon perfect I find and since there is three bricks it lasts a few months if you do the once a month cleaning. I would try to hold off on the feeding till he poops again so it doesn't make him worse. And if you do the honey trick you want it to be pure honey like the billy bee stuff. If you feed him in a separate enclosure is there a chance the pacman food wasn't expanded enough after the water was added and it expanded more in his stomach. I have never used it so I'm not 100% sure how it works. Or as I mentioned he might of thought a piece of moss was food and he ate that.