Not much is known about the effects of bromide in a reef aquarium. I've not done a literature search of known toxic levels in seawater.
Bromide is discussed here:
The Halogens Part I: Bromine in Seawater and Aquaria
http://web.archive.org/web/200306261...io/default.asp
and
What Happens When Ozone is Applied to Seawater?
http://reefkeeping.com/issues/2006-03/rhf/index.php#6