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Peroxide overdosing incident

Mark_C

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Last night i decided to spot treat some hair algae with 3% hydrogen peroxide (thanks Sponge).
I poured approx 7oz into a bowl (its what was poured out, and I was too lazy to try to get it back in the container).
Intent was to mix some tank water with it and use a baster to hit the algae, dumping out the excess peroxide.
Of course, within seconds of balancing the bowl on the rim of the tank it went in.
I didn't dose the recommended 1ml per 10g, I dosed 49.5ml per 10g.

All corals - shrooms, zoas, palys, sps, lps, gps, sos, got, etc... closed up instantly.
Panic!? Fear!? No. I just figured that, if I can dip zoas in 100% peroxide, a cup of the stuff shouldn't doo too much damage.

So I took the top off the skimmer and ran it up to oxygenate the water and waited.

This evening on return from work everything is fine.
All corals are open, and a few of them actually look much brighter.
All fish and inverts fine.
All algae reduced by about 50%.

Won't do this again (just yet), but goes to show that a 50x peroxide dosing accident shouldn't cause too much worries.
It's actually made me consider running an experiment of 5mg peroxide per 10g over the course of a week to see effects.
 
Wow. I read that on the edge of my seat. I actually stood up at one point. Phew. Very happy it worked out. I have used peroxide often and only had benifits. But knowing less than nothing about Corals I was sweating during the read LOL. I can now go to work with a smile. Have a great day Mark.
 
Oh and when you said 100 percent I nearly had a heart attack. I use lab grade 30 percent and that stuff will melt your face off. Must be cut to use. Then I realized you were referring to 100 percent of the 3 percent. Guess I shouldn’t read first thing in the morning haha.
 
I spot treated and then dosed hydrogen peroxide (less than recommended amount every other day, for 7-10 days) a while back and had a bad experience. Snails died over the course of a few weeks and my chaeto suffered, then I had a strange bacterial outbreak on my rock. Resembled Dino’s but definitely wasn’t that. Lost my fighting conch and hermit crabs too, but urchin and linckia star survived. Corals initially closed up from treatment but re-opened within a few hours each time. I lost some small colonies down the line to the bacterial outbreak because I didn’t do enough to control it. Eventually I hunkered down and put a lot of time in, more frequent water changes and rock brushing, lowered the light duration, and put in new chaeto and pods in my fuge. Noticed my snail population picked back up and all is good. Very good in fact.

I’ve read a lot of info in support of hydrogen peroxide spot treatments and even regular dosing for algae outbreaks but I won’t do it again. I’ll stick to water changes and manual removal if at all possible. Could’ve been something else thaf caused the problem but sharing my experience. Good luck.
 
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I can see where the Cheto was affected. Makes sense. And inverts. For sure. I don’t understand the bacterial outbreak at and think that may be a coincidence. I completely agree waterchanges and maintenance is always the best way over any chemical. But sometimes that just doesn’t do it. I would add that I have rarely put peroxide directly into tank. (But I have with no ill affects) what I usually do. If I have a large leaf plant that is getting algea on its edges. I pull the plant dip in solution and then put back. In about five days plants perfect.
 
Yeah, I never understood the outbreak either but the timing lined up, and I had not added anything new at that point for a few months. It may have been an after-affect of the die-off since I had a lot of snails that bury in the sand, plus I lost some large snails too. I tried to remove the larger ones but definitely didn’t get them all. All I can say is I was glad when it was gone and the hair algae came back! Glad to say neither is an issue anymore.
 
You are probably right that the out break was an after effect of the die off. At least that makes sense to me :) very glad you no longer have the problem. I would like to be clear to all who read this. I am mearly sharing my experience and in no way am I qualified to dispense “advice”. I super enjoy this forem and look so forward to reading others experiences... happy reefing.
 

DangerDave

NJRC Member
I think you’ll be fine. I’d be most worried about nems. They get pissed.

You didnt need to remove the skimmer cup, when the h202 reacts in the tank, you end up with water, and the extra o2. I run an oxydator 24x7, and dose direct on occasion.

A couple days before you came over i forgot to dilute to 3% when dosing, and using 30ml of 12%. not as high as what you just did, but my only effect some pissed off nems for a couple hours.
 

MadReefer

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I peroxide dosed when I had Dino's and it did rid some of them and other algae, esp cheato. Some corals were okay others not.
One thing i did notice was that any new animal introduced would die within 48hrs. I assumed it could not handle the peroxide for some reason. Yes, I did acclimate.
Fingers crossed but think my Dino's are gone........for now
 

Mark_C

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Everything is open this morning with about 50-60% reduction hair algae and no diatomes on the floor.
If possible, the zoas seem to have perked up a bit. All inverts (including more delicates like anemone crabs) are out and scavenging.
Seems there's no concerns.
IMG_8871.jpg

Dave, if you look on the right side just under the utter chaos colony, thats the duncan opened up. The yellow deaths are just in front of the cleaner shrimp on the left, red monti top left and yellow palys just under it.. All acclimated great and survived 'The March Burning'. Cheers.
 
You are probably right that the out break was an after effect of the die off. At least that makes sense to me :) very glad you no longer have the problem. I would like to be clear to all who read this. I am mearly sharing my experience and in no way am I qualified to dispense “advice”. I super enjoy this forem and look so forward to reading others experiences... happy reefing.

That’s what the forum’s all about! And that’s why I like coming here myself. I definitely had a different outcome than other folks, so I may have done it wrong or just more evidence that each system does their own thing. Sharing my experience hoping maybe it’ll help and maybe someone who knows more than I can figure out what went wrong.
Either way, glad to read what everyone’s experienced, and thanks for sharing, Sponge!
 

Mark_C

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Week out update.
Everything is fine with one exception.
I had adopted my first duncan, which was moved into the tank and doing well acclimating, but the environment change magnified by the tons of peroxide hit it hard. Transferred it to another tank in hope for revival.

There is something odd going on which I've never experienced, and I'm in two minds of opening a new post.
For whatever reason I'm experiencing tremendous growth in the tank. Like, crazy growth. Like 1960's sci-fi growth.
SPS has doubled in size in the past 2 months, jawbreakers have gone from size of a dime to size of silver dollars, zoas are now fighting for space, monti are spreading fast enough to block light.
I have no idea what brought this on...
[errrrrr...] As I type this I realize I switched from Red Sea Coral Pro to Reef Crystals 6 weeks back...and I'm now curious.
I like RSCP better based on numbers and I just bought a new bucket to swing back to it, now I'm debating.
 
That’s interesting. I have never heard of switching from one good salt to another good salt causing. Excelerated growth. Really odd since Red Sea pro has elevated levels but I guess it just shows how little I know. Hahaha
 

Mark_C

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May not be the salt change. Might be age of tank, temp, or other factors.
Started to monitor temperature last week. May break out the kits to monitor all the other stuff just to see what's going on (I normally don't monitor).
May never know and not too bothered, but its interesting.
 

DangerDave

NJRC Member
That’s great to hear that there were no effects. The Duncan doesn’t count. They’re super hardy, I’m sure it’ll come back (or I have a spare for you) :)

Even better is the growth, that’s what we all want even when we don’t why it’s happening!
 
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