Blackout with Zoas, how long?

[ihateSpirorbids]

I've got dino issues and some kind of green slime algae growing all over my tank. I've done a blackout for nearly 2 days, but caved into giving in some light because I was afraid my zoas would die. I just started with zoas, and only have a few super tiny heads on a frag so far, so I feel they're super delicate.

How long would you guys feel comfortable with doing a blackout? Did any of your zoas die?

 

[Bucs20fan]

Ive got acros and ive done 72 hours with no ill effects. Theyre ticked off obviously, but still alive. Remember, almost all of these corals come from regions with massive typhoons/hurricanes that block the sun for up to 10 days in some cases.

 

[Edgecrusher28]

I have done many 4-5 day blackouts dealing with algae in the past without issue (Zoa grow out/frag tank). On the other hand, I've lost plenty of zoa's due to massive algae overgrowth.