In article H6oba.41568$F1.2113@sccrnsc04, "WD" writes:

My anubias, swords, and Java fern have been growing wonderfully for a
couple months now. I have been using Flourish and Trace, more or less to
package directions. Lately, my anubias has been turning a reddish-yellow. Is
iron deficiency likely? None of the local LFS have iron test kits, in fact
most of them have no idea what I'm talking about. Mail order only option.


I've read that when you see yellowing/browning leaves in only slow growing
plants (like anubias) it can actually be a symptom of an excess (poisoning) of
nutrients. Fast growing plants would not be affected. The fast growers will
yellow first when there is a nutrient deficiency where slow growers have more
nutrients stored.
-Paraphrased from Peter Hiscock, "Encyclopedia of Aquarium Plants"

Are you adding CO2? I would think poisoning would be more likely if you
aren't.
Cris