Newbie Here, Hopefully this has not already been discussed or I will feel like an idiot. (My searches all came up empty.) Are there any safety issues with pouring used pen flush down the drain? Is it safe for ground water? Or should I be discarding it with the used motor oil from my husband’s race car? I used the usual fountain pen brands and I also use Calligraphy inks. Any advice would be appreciated. Flourish, Casey Haven