Did I just Kill my coral?

[Gary S]

I added H2O2 tp try and remove some nuisance algea and no more than a minute later my duncan retracted and is continuing to shrink. Any advice will be appreciated.

 

[madweazl]

Duncans can be fairly testy sometimes; I dont see anything to be overly concerned about in the pictures above. You may want to look into how much hydrogen peroxide you're using in the future though.

 

[Gary S]

Duncans can be fairly testy sometimes; I dont see anything to be overly concerned about in the pictures above. You may want to look into how much hydrogen peroxide you're using in the future though.

5ml in a 13.5 gallon tank, to spot treat.

 

[bw777]

I thought it was 1 ml per 10 gallons. I could be wrong though.

 

[reef lover]

1 ml per 10 gals 2 times daily....thats probably his problem....water change if you can or wait it out.

 

[JoshH]

I would say the spot treatment did it, you're spot treating so it's technically 100% and not diluted. I've done it with my duncans but outside of the tank and rinsed not long after so there was no ill effects. They will recover it will just take some time, if you are concerned than as @reef lover suggested, a good water change will speed things up

 

[OriginalUserName]

I'd wager it will be fine. Looks ticked, not dying.

 

[Gary S]

Its definatly recovering now, so thank you all! Just gotta see what that brown algae is!!! Ive looked though a microscope, but it doesnt even look like dino, but gets stringy like it...

 

[Dom]

5ml in a 13.5 gallon tank, to spot treat.

Yeah... that is a big dose for such a small tank.

 

[Brew12]

Just as an FYI, an overdose of H2O2 is hard to correct. The actual H2O2 breaks down very quickly once dosed to a system. The reason we see a longer impact on ORP is due to the organic compounds that are impacted by H2O2 dosing.

In the future, I would recommend diluting your H2O2 before adding. You don't want much more than 1ml per 10g so for your system I would max at 1ml. To make it easier to work with, add 4 parts RODI to 1 part of the 3% H2O2 so you can add 5ml of the diluted mixture.

Hopefully things continue to recover!

 

[Reeferdood]

FWIW,
when I used H2O2 my duncans always reacted almost immediately the same way as yours. I am sure it will be just fine in an hour or so. Like Brew stated, dilution is the best solution when using H2O2..
Good luck!

 

[ArowanaLover1902]

Don't use duncans as a sign of anything, they're really strange. Mine was happy and thriving for months in a place in the reef then he switched to hiding almost all the time, I assumed it must be the parameters (which all tested fine), but when I moved him, he puffed right up and is doing great again, long story short, duncans dont always make sense.

 

[Lunar Mike]

Looks normal, mine always do that about a couple days after feeding. Doesn't last long.

 

[fishplace817]

I would do water change and redose it slowly through it the day... you may shock it

 

[Reefhabit]

The hydrogen peroxide breaks down fairly fast. I wouldn't worry too much. Duncan corals are pretty hardy and it looks like its upset but it should be fine