fish are dying and need help and canister filter question

[sangigt2]

i have had a yellow tang and clow fish die in tank recently and i dont know why. I have 2 wrasses and a couple damsels and they are fine. i dont know whats wrong with my tank, i just added a refugium to my tank the other day, if i dont have a sump do i still need to keep my canister filter in my tank or can i get rid of it

 

[AiredaleReef]

well it could be many things....check your parameters and do a water change. also a 55g may be too small for the tang.

 

[HPD Turbo]

Well a CF is a bad idea for SW I said get rid of it. If you allready have a fuge you can make some mods to make it a sump/fuge.
Do some water changes with RO/DI and make sure on your parameters.
Carefull with the size and the tangs, they need a lot of room.
Good look.