Yeah I started this thread not really caring too much about the salt I use. I use Oceanic now said:That's an interesting comment, and it reinforces a thought that was lurking in the back of my head. I recently changed salt formulations (same brand) and had an outbreak of hair algae. While fighting it, I blamed it on everything except the salt. I never thought the salt could be the culprit. I increased water changes to try and reduce nutrients but it kept getting worse. I eventually gave up and practically ignored my tank except for feeding and water top-off for 2 months. The hair algae got so thick you could hardly see any rock. I finally pulled the algae out again about a month ago and to my surprise, none has grown back. I performed my first water change in about 3 months last week using the same salt and hopefully it won't return. If it does, the salt may be to blame. I never considered a bad batch of salt being high in PO4.
Gary