Your water parameters are OK, within range. I would not adjust them at all. If you do, do a little at a time over a long time. Sounds like you have a placement issue. Mine does not like strong current. I've got a T5 HO light and it's mid way in the tank. Maybe relocation and a little food is all you need. Also I'd look into doing away with the sock filters, nitrate factory. I use them after a weekly cleaning for a couple of days then take them out. Well i guess I should ask if you have live rock, live sand to filter your water before I suggest you take out your socks. Don't want to interfere with your biological filtration. Also how often do you clean your socks and how? Also is there anything close that might be stinging your Acan, ie an anemone, or another coral..... Take a photo of your setup and post it though photobucket.com. Not to argue but your water is not the problem IMO and i think if you start trying to adjust things it's only going to creat other problems. The only thing I could suggest is to try to lower your nitrates. I think the main reason nitrates being elevated is over feeding and not cleaning very well, husbandry. Socks filters did elevate my nitrates but that problem has been resolved by removing and not feeding as much as well as better cleaning. Sorry about your plate also. It sucks when you loose an animal.... Good Luck
My water parameters are: Salinity 1.023, Ammonia 0, Nitrites 0, Nitrates 0, Phosphates 0.03, Temp 79, Ca 460, Mg 1360, Al/Kh 8/2.86
PH 8.2
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