291493 Wed Jan 08 08:31:02 -0800 2003 5 27 General Chowhounding Topics 0 1586452 I got a Butter Bell just around Christmas (one of those things that let you leave butter out at room temp by inverting a crock of butter into a container of water, thus creating a vacuum seal). I have followed the directions about replacing the water every few days, but I find that after a while the bell develops a sort of blue/green stain that I cannot quite identify. It may be residue from my water, which comes from a well, but I have an iron filter, so I would not expect that to happen. Any ideas? Wed Jan 08 08:31:02 -0800 2003 0 James G 1 1586453 If you had chlorinated city water, I would have suggested that chlorine by-products were the problem. Iron stains are red. Does the stuff scrub off when you wash the bell? How long do you go between emptying this out and washing it? You might be breeding some sort of blue-green mold. Wed Jan 08 08:43:20 -0800 2003 1586452 0 ironmom 2 1586455 It is easily wiped off and seems to be attracted only to the bits of porcelain that hit the water. Wed Jan 08 08:59:59 -0800 2003 1586453 0 James G 3 1586472 Ceramics are insulators, however, porcelains are made with metals so there could be a small electric charge of some sort. Is the blue green color close to the patina a copper roof gets? You may have dissolved copper salts in the water. Wed Jan 08 11:20:04 -0800 2003 1586455 0 muD 1 1586459 I've used a butter bell for a few years now, filling it with NYC tap water, and I've only seen the blue-green stain when I've been neglectful about changing the water. Wed Jan 08 09:38:15 -0800 2003 1586452 0 Susan Hope 2 1586517 Mine's ceramic and I've had it for about a month. I change the water every other day, and wash both sections whenever I've scraped the last of the butter out of it, and have had no problems with residues. In the summer I plan to change the water daily. BTW, last winter I kept the butter out on the counter in an old-fashioned covered glass butter dish, and it was fine. Wed Jan 08 13:06:59 -0800 2003 1586459 0 C. Fox