fading sps

[christyf5]

I'd say the problem with his corals isn't that they can't utilize Ca because of low Mg levels. They're being iodine dipped 24/7

Originally Posted by Jim Barry

Christy,


I have only been testing for Iodide.

Using a Salifert test kit, the color turns black. This is right off the chart. The darkest colour on the chart is light blue (.20)

I am really confused between Iodide, Iodate and Iodine.

Well I'd say that if you've still got a whack of iodide in your tank, theres your problem. Iodine has alot of bacteriocidal activity, could be its just doing an incredible number on your zooxanthellae reducing their numbers and causing mass bleaching in the tank.

Iodine (I) (commercially prepared supplements ie. Kent/Seachem etc)
Iodide (I-) (this is the state at which Iodine can be taken up by tank critters)
Iodate (IO3) (I'm not sure where this one fits in, chemistry hurts my brain)



Ok here is the reading

http://www.reefs.org/library/article/e_edelman2.html
http://advancedaquarist.com/issues/mar2003/chem.htm

Hmm, that second link indicates that algae loves iodine. Fling some chaeto in there/start up a refugium and see what happens, maybe it will suck it all up



Just a thought, as a test, take out a couple of smaller pieces of rock. Put them in a rubbermaid tub with new water, heater and powerhead. Leave them in there for approximately a week. Then test for iodine. There is a possiblity that the iodine has been absorbed by your rock and is leaching out.

Another idea (which sucks immensely) is to restart the tank with all new water. Even though you've been diluting the tank by doing water changes, your water changes are really too small to make any noticeable difference in your iodine levels in the short term anyways. You'd have to do incredibly huge water changes to get it diluted enough for stuff to live comfortably in it anytime soon.

Just my two cents

Christy