Filtration

[florida shark]

I am in the process of building a 550 gal tank for sharks and a couple of groupers i have in my 125. What is the best filtration system to have in a tank this large? Also is it possible to purchase a denitrifier that would eliminate water changes? My Lfs said yes but some people told me you should do water changes anyway. Any advice would help. Thanks!

 

[cboyfan2020]

i would think a large sump system would be best maybe with a refuge incorporated cause sharks can be very messy. I think a water change would be good just for the fact of trace elements but thats JMO