Bryopsis in my fish QT

[Tiny Ocean]

Hi all,
I have a fangblenny and a chromis in a 13 g quarantine tank, they have 2 weeks to go before heading for the DT. What I thought was a lovely, big snacky patch of hair algae for future fish is apparently actually a Bryopsis (based on its branching habit and my microscope observation of lack of segments). The blenny is nice and fat, the chromis still tiny and a bit thin but both eating great and very active. I don't want to stress them.

My question is, should i treat the QT now? Wait until I move the fish? Will moving the fish likely introduce this pest into my DT with the little bit of water that goes in? What would you do?

 

[Spare time]

Just run the light at the lowest setting. Most people I know don't even have a light on their fish qt outside of ambient room light or it's so weak that algae won't grow very well. Are you running any meds in the QT?