Accidental hydrogen peroxide dosing

BurtMacklin

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I have a 65 Gallon tank 12 months old. 20 gallon sump.

I had some 3% hydrogen peroxide lining the bottom of a 5 gallon bucket 2 days ago to kill some algae. Forgot to wash it out, filled the bucket with RODI then 24 hrs later added salt and stirred for another 24 hrs. I added the water 10 minutes ago. All the corals are closed up and a giant Mexican turbo snail fell off the glass. I have a lot of sps, LPS, and zoas. 2 Clown fish, 2 cardinal fish tail spot blenny, royal gramma.

Do I need to do a massive water change? I have 5 gallons getting prepped right now and another bucket filling with RODI

I also have a 10 gallon invert tank for raising snails where I can move fish if needed.

What can I do?
 
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The normal dosing is like 1-3ml per gallon. How big is your tank? From what I have read, H202 breaks down when its exposed to light and sits out in the open.
 
When I dosed h2o2 initally most corals did close up but opened normal the next day.

A water change will be nice but might not be needed. The h2o2 should have degraded quite a bit being exposed to the air.
 
you need a lot of hydrogen peroxide to kill a tank, a water change is always a good way to get anything out though. How much do you actually think you added? Also the hydrogen peroxide should have been depleted after 2 days leaving you with just water in the bucket, if it was uncovered
 
Hello

If the hygiene peroxide is a residue in the bucket, there should not be any issue.

Looking at you tank volume, if you were dosing hygiene peroxide, you should not be dosing more the 14 ml a day or two 7 mil doses before the light come one and after the light turn off.

FYI once the hygiene peroxide bottle in opened, the shelf life is 6 months. Another reason for my answer above, hygiene peroxide breaks down pretty quickly.
 
How much peroxide was in the bottom of that bucket volume wise? If it wasn't a lot, my guess based on your description that a fair amount of if decayed before you added new water
Tough to say in milliliters, maybe 100-150ml. It was just enough to coat the bottom of the bucket. I would hope a lot decayed, but all the corals are closed and retracted polyps and that snail fell off the glass. I was surprised there was enough left to upset the tank this much. Also worried about bacteria die off and ammonia.
The normal dosing is like 1-3ml per gallon. How big is your tank? From what I have read, H202 breaks down when its exposed to light and sits out in the open.
As stated above 75 gallon system when rocks and sand accounted for. The water had a heater and power head in it with the cap closed over, but not tight.

When I dosed h2o2 initally most corals did close up but opened normal the next day.

A water change will be nice but might not be needed. The h2o2 should have degraded quite a bit being exposed to the air.
I'll still do another 10 gallons of change tonight. It should have degraded, but still seems to be hurting the tank.

you need a lot of hydrogen peroxide to kill a tank, a water change is always a good way to get anything out though. How much do you actually think you added? Also the hydrogen peroxide should have been depleted after 2 days leaving you with just water in the bucket, if it was uncovered
It was covered over with the bucket lid, but not tight as power cables were routed out of it. I would estimate maybe 100-150ml hydrogen peroxide
 
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Hello

If the hygiene peroxide is a residue in the bucket, there should not be any issue.

Looking at you tank volume, if you were dosing hygiene peroxide, you should not be dosing more the 14 ml a day or two 7 mil doses before the light come one and after the light turn off.

FYI once the hygiene peroxide bottle in opened, the shelf life is 6 months. Another reason for my answer above, hygiene peroxide breaks down pretty quickly.
I would estimate around 100ml was in the bottom of the bucket, still wet. Not residue. Brand new bottle of hydrogen peroxide.
 
Assuming 150mL of peroxide and no degradation, the new saltwater had 0.02% peroxide. After a 5G water change in a 75G net water system, the peroxide would then be at a 0.001% concentration assuming no degradation. By my math, that's roughly the concentration you'd get from jsker's suggested dosing
 
I would estimate around 100ml was in the bottom of the bucket, still wet. Not residue. Brand new bottle of hydrogen peroxide.
as @dedragon stated, you would need a whole lot of peroxide, on a steady dosing to do damage to the tank.

How do your corals look, if your corals look good then. I would not be concerned.

If you would like to be precautionary, run a little carbon for a day or two. I would suggest two cup in a nylon stocking in the flow, in your sump. The carbon will filter out any contaminants.
 
Just found an old thread where I dropped an 8oz cup of newly poured 3% HP into a 40g tank.
You'll be surprised at the results. Don't Panic.

 
as @dedragon stated, you would need a whole lot of peroxide, on a steady dosing to do damage to the tank.

How do your corals look, if your corals look good then. I would not be concerned.

If you would like to be precautionary, run a little carbon for a day or two. I would suggest two cup in a nylon stocking in the flow, in your sump. The carbon will filter out any contaminants.
Corals are super ticked, especially the softies and LPS. Sps retracted polyps. I normally run 1/2 cup (8 tablespoons) for my system and just swapped that out for fresh. You think I should do 2 cups for a couple days?
Assuming 150mL of peroxide and no degradation, the new saltwater had 0.02% peroxide. After a 5G water change in a 75G net water system, the peroxide would then be at a 0.001% concentration assuming no degradation. By my math, that's roughly the concentration you'd get from jsker's suggested dosing
I get 0.001% with 150ml in 75 gallons. A 5 gallon change is only a 6.6% change by volume which would drop it to 0.0009%

(C1) (V1) =(C2) (V2)
 
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peroxide dissipates rather quickly and any closing up would be temporary. Its mainly water and a question was raised about dosage/ / / / its 1ml per 10 gallons
 
Turn the lights on, kick the skimmer into high gear, toss in extra carbon , a polyfilter, and then grab yourself a glass of gin and try to relax as the storm passes. gl
 
Corals are super ticked, especially the softies and LPS. Sps retracted polyps. I normally run 1/2 cup (8 tablespoons) for my system and just swapped that out for fresh. You think I should do 2 cups for a couple days?
Yes. Do you have any vitamin C at the house, break up two tablets and toss them in the filter socks. This will help the corals and fish to reduce the stress in the tank.
 

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