Hi! I am new to this site trying to find out as much info as I can! 
I adopted my 8 month old Holland Lop rabbit from a local Humane Society almost 4 weeks ago. He was neutered on Jan 16, just a few days before I brought him home.
At first he seemed to have decent litter habits. (unless I just wasn’t noticing the pee on his blankets??) Not perfect, but he did okay. For the past week or two he has been peeing outside of his litter box, a lot. He is currently in a large cage in which I have his litter box that takes up about 1/3 of the space on one side, then a towel, flannel blanket, and fleece blankets on the other side. I leave the cage open when I am home so he can come and go. He only occaisionally will pee outside of his litter box, but does poo randomly around the room. I would like to change this habit too!
I notice he does use his litter box for pee, but also pees all over his blankets too! Another thing, he seems to drink a lot of water. He has a 20 ounce water bottle that I fill morning and night. I am not sure how much a rabbit should drink.
I am just wondering how to train him to only pee in his box and not all over his blankets!
Sorry this got so long winded and thanks for reading! Any feedback would be greatly appreciated!!