I recently found an article that said in salt water aquariums mangroves will remove magnesium very quickly. If your mangrove leaves are yellow or hard it is b/c there is not enough magnesium in the system and the plant is stressing out. Just wanted to get this out there. Any thoughts? BTW I'm going to test my levels tonight to see if there is a difference between now and when I didn't have them.

Here is the article it is long but very informative.
http://toptropicals.com/html/aqua/pl...ngrove_eng.htm