No worries there, been doing that part for quite a while so still doing water changes in conjunction with the AP. Not sure on exact amount that's ok for the eel or how much is necessary for the plants. Still trying to find info. Usually hit up my favorite fish forum for fish questions but they seem to have a dim view on the benefits of epsom salts, last guy who mentioned it got so ridiculed he quit I think, but never got a straight answer. They do have knowledgable people, but not all and a lot of restrictions on topics that are allowable.