I am trying to compile a comprehensive list of fountain pen safe notebooks. From my experience there seems to only be a few notebooks that are truly fountain pen safe.
Apica-A Japanese notebook company. The paper is absolutely wonderful. Very smooth and very thin. Even though the paper feels very thin, there is no bleed through even with a bold nib pen. A great selling point is they are very inexpensive. You can pick up a three pack of notebooks for around $9. European paper has a nice selection.
I think a lot depends on how wet your pen writes. That being said I use moleskine.
I like moleskines a lot, but unfortunately I find the paper quality is not consistent for fountain pen use.
Funny. I've been using them for the past decade with most of the 50 or so FPs in my collection and I've never experienced that. Which version of Moleskine are you using?
Leuchturm 1917 is an excellent brand with good paper and well-made books, and for fountain pens (http://www.leuchtturm1917.com) RK
I've had good luck with the Apica, and the Clairfontaine, but the Rhodia is my favorite. I always have a Moleskine or two around, because, well, they are just what a notepad should look like. The shape, the size, the color, the little pocket in the back, by far the most dignified looking pad to take out at a Boardroom table. Unfortunately with any nib broader than an "Extra Fine", with any of the inks I favor, the Moleskine paper shows through enough that I can only use the "front sides" of each page. I have friends that are big Moleskine fans, and they simply choose nibs and inks that get along with that paper. To me it's easier to use the Rhodia, and any nib and ink that I please.
I'll have to try those. I tried some little "Markings" notepads from Wal-Mart. Little shirt-pocket sized ones. They come 3 in a pack, in lined or gridded. They look a lot like the Moleskine, but with the pocket in the front. They are perforated. (cue the angelic choir) and they are cheap. I liked them so much, I bought the larger (I journal with A5 size) size and they were terrible. The same cover, made the same way, but the paper was worse than cheap copy paper. Every ink I tried with a medium nib looked as if it was done in watercolors. Now I assume the paper supplier is a crap-shoot, and I'm afraid to buy any more little pocket ones.
My best is the Moleskine with the acid free paper. Especially the large notebooks I use for study journal and whatnot. I use a Parker urban and it flows well on the paper.