Quote Originally Posted by Mr_Cool
Ok. So I've only dosed the iodine twice. The instructions on the bottle said to give one capful every 4 days. It was a Kent Marine starter pack with Calcium, Strontium and Iodine. I guess I'll just toss the Iodine.
The best rule of thumb I have ever heard is "if you can't test for it, don't dose it." Especially something as potentially toxic as iodine. I used to dose iodine as well. I stopped and never noticed a difference. I think light makes a lot bigger difference in Xenia growth. The last time I read something about iodine and Xenia they came to the conclusion that Xenia does absorb iodine, but it doesn't necessarily need it. It also absorbs a lot of toxic heavy metals. That's one of the advatages of something like a Xenia fuge, it acts like a water purifier. That doesn't meet you want to dose lead, chromium, mercury or cadmium to your tank though.

In my experience, the key to growing Xenia is light, pure and simple. The more the better. It grows like a weed in one of my tanks under MH, and I can barely keep it alive in my other tank under fluorescents.