I use the cypress bark, mine is almost exactly the same size... 345g and 30ish long. I order the 8 or 24 quart bags from amazon ($11-$22) and they last three-six weeks or so. When he urinates, I change all of the bedding around the area that is damp (usually 1-3 scoops from a cat litter scooper) a little more when he defecates. Then once a month I remove 50% of the bedding and mix fresh back in. He's in a 40 gal tank, so I still have a lot of clean mulch at the end of the month. It's really not that different from scooping a cat litter box.