Starfish - skip QT? How concerning is white tip?

[NancyFish]

I got a biscuit starfish, tried qt, (today) day three a white tip appeared, yesterday he was moving good. I’m unsure wether to put him in the display because some say they don’t need qt, or if this even more reason to not do it. I feel bad for the little guy. Increased his oxygen this morning, Going to try some algae wafers soon.

Three hours later, progress:

 

[vetteguy53081]

These biscuit stars are one of the more challenging and require optimum water conditions, feedings and stable tank. No high phosphates/nitrates and proper salinity level