Qt questions

[tmkx3]

I have a tang that has ick. I guess I am gonna go hypo. I have a 55g I can use but It isn't set-up yet. I have an hob on the main but It has only been there a month. I am concerned about water qualty in the qt due to no biological filter. I have also read about ph problems during hypo. Is this because of ammonia spikes? I am considering doing the treatment in the main and removing the inverts and lr. My tank is 125g will the larger size help with water quality or will due to all the water changes the 55g be a better choice. I also have 2 perculas,3chromis,a coralbeauty and foxface.

[Steven Pro]

I would prefer to perform the hyposalinity treatment in the 55. Just move the HOB filter that you have on the display to the quarantine along with the fishes, keep a close eye on ammonia levels, and add extra buffering compounds to help maintain pH.