Here is the biggest selection of info in one place about diffrent filling systems.
http://www.richardspens.com/?page=ref_info/vac_diaphragm.htm
As for your Ligero, it depens if you have a throw away refill in the pen or a converter. Most likly you just have the refill. You can go as easy as just buying new refills, but that gets old fast. It just came to light about possiable problems with the Schmidtt converters that are sold for our kits. However, Lou has some better converters that are better looking and will fit. The cost in fact, is about the same and well worth the price.
I do suggest you flush the pen and new converter with a water to ammonia solution (90% water to 10% ammonia) to clean and flush the pen and the new converter. The converter will fit in the pen just like the refill, but allow you to use bottled ink.
Bottled ink is much more for your dollar, in fact one could make the point that it is enviromentaly friendly. The fountain pen itself is not tossed in the trash when empty, not is the ink delivery mechanics. The ink itslef is in a glass bottle that can be recycled as well. [
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I recomend that you take advantage of the ink sample program at:
http://shop.peartreepens.com/main.sc for just $4.00 shipped you can buy four samples of ink to test out colors and brands. Noodlers has the best bang for the buck, my favorite writing inks are Visconti and Diamine. If you want to ask me to recomend one based on a color range, just ask.
The Ligero has the larger nib and I "think" that Lou has the larger nibs with diffrent width lines if you look into it.
