Now those were a good investment that I wish were around in the "Mrs wages" days. I've never used iron but ca/alk/ultra low phosphorus should be on the shelf near any tank with acros.
Maybe the iron one was originally for FW and they repurposed it without tuning for SW?
i bought a iron and i was trying to see how much dos it has i cannot even tell, i talk to hanna he said send it back lol I got lazy it was 50$