**HELP** Hot water change and Hydrogen Peroxide

[eddie462]

I just did a 50% water change and while the tank was half full I was squirting in h202 to kill algae. after the water change the temperature rose to about 78 F when it was at 75 F. I added about 3 ml of Seachem Prime. My reticulated hillstream loach died. It was swimming and spinning. I moved it to a nearby 10g that was about the same temperature from a 50% water change without dosing h202. It is sitting on the substrate and not moving so I think it died. My angelfish and 3 guppies are at the water’s surface gasping for air. My Ornate Rainbowfish and penguin tetras have been fine and not gasping. 
 

I added in that never clog air stone in the right powered by a topfin rated for 10g. I did another 50% and I did not add in anymore prime as I know that uses up oxygen. The water coming out of the tap this time was noticeably cooler. My water has 1.3 ml of chlorine per gallon. My guppies are at still at the water’s surface while my angelfish will go up to the surface once about a minute. After she goes up, she swims back down with her head pointed up and she’s leaning slightly to the right. 
 

is there anything else I should do besides keep monitoring them?

[eddie462]

I should add that I’m in eastern standard time and it’s 8:10pm right now. The light is still on and it normally turns to sunset at 7:00 and off at 8:00. I’m hoping that her lethargic behavior is just from her being tired. She has occasionally had a short burst of energy. If I put my fingers by her she will slowly swim away from them, but I don’t want to keep doing that and stressing her. 

[Gideyon]

I'm not familiar with the use of hydrogen peroxide in an aquarium with fish but I can't imagine it being good for them.  Even for a human, they stopped recommending it for wound application because it dries out the skin too much.  Imagine what it would do to fish gills.    But I'm not a scientist... I don't know. 

The reaction it has with the algae is likely raising the temp.  

[KittenFishMom]

If you kept the water you took out for the change, you might try putting the fish in that. (I keep mine to water plants.)

If you did not keep the old water, you might try charging out some of the water with distilled or purified drinking water. 

If you want to cool the water, you can put ice (or anything frozen in your freezer) into a zip lock bag and put it in the water for short periods of time, while monitoring the temp closely. Cool water hold more oxygen than warm. but changing the temp quickly is hard on the fish.

Peroxide acts like bleach at full strength. It oxidizes and kills germs.  If you were spaying it on the glass to kill algae, maybe too much got into the water.  

I have diluted peroxide and used it to raise oxygen in a water that had low oxygen due to heat. In small dilute amounts it is a life saver for fish that are suffocating. It breaks down into O2 and water.  I've never used it full strength in a fish tank.

[KittenFishMom]

A very random thought that might help is to take some tank water out and fill a blender half way and run the blender to get air into the water and put it back in the tank. This might help get some chlorine out too. I don't know if it will help, but it should not make things worse.

Please let me know how things are going.

[laritheloud]

I'm so sorry this happened. I suspect the hydrogen peroxide is the culprit and not the warm water. I would add more prime to that second water change since you did another 50%. Aside from moving them to a tank that hasn't been treated with h202, there isn't much else you can do but give them clean water and wait. @KittenFishMom has several good ideas to try aside from waiting. Good luck, and I hope they recover.

Edited December 27, 2021 by laritheloud

[Gator]

@eddie462 and @Gideyon; back in the '80's while still living in Orlando, FL, a Guppy Society recommended using Hydrogen Peroxide to increase the oxygen levels in aquariums. On the outside it makes sense since Hydrogen Peroxide is made up of two parts Hydrogen and two parts Oxygen and would bond with those same molecules in the tanks water, but I never did this for the same reason @Gideyon stated, Hydrogen Peroxide may damage the gills of my fish. I do use Hydrogen Peroxide to kill Blackbeard algae, but the dosage is sprayed on the algae, is in a much smaller dose that what was recommended in the '80's, and my water temps do not rise because of it. 

[RadMax8]

How much H2O2 did you add? In my experience, you’ve got to be careful with that, as it can oxidize the gills of the fish (think what happens when you put H2O2 on a cut) and cause irritation or damage. 

Keep an eye on your fish, I would probably do another water change. 

[Odd Duck]

I also would suspect the peroxide, but I have used 3% peroxide at up to 3 mls per gallon (based on the actual water volume in the tank, not just based on tank size) with no deleterious side effects to the fish multiple times.  I use this with a full tank with no power filters running (I leave the sponge filters running to have some aeration during treatment) and use a syringe and tubing to “drizzle” the peroxide directly on the algae I want to kill.  Usually I can do a lower dose focused just on small areas of algae.  I leave the power filters off for 10 minutes monitoring closely for any signs of stress in the inhabitants.  Turn the filters back on and run everything as usual.

If your water volume was low during the water change, you have to dose based on the water volume that was actually in the tank at the time or your concentration of peroxide in the water could get much too high and damage gills.

I think you’re doing what you can - aeration and steady temps, tincture of time.

[KittenFishMom]

@eddie462 I hope things are looking better in the morning. 

Many people have replied saying they have used peroxide in they tanks in one way or another.  You were acting in good faith and noticed and reacted to the problem immediately. It doesn't get much better than that.  Hang in there !

[eddie462]

On 12/26/2021 at 9:22 PM, Gideyon said:

I'm not familiar with the use of hydrogen peroxide in an aquarium with fish but I can't imagine it being good for them.  Even for a human, they stopped recommending it for wound application because it dries out the skin too much.  Imagine what it would do to fish gills.    But I'm not a scientist... I don't know. 

The reaction it has with the algae is likely raising the temp.  

 

On 12/26/2021 at 10:49 PM, KittenFishMom said:

If you kept the water you took out for the change, you might try putting the fish in that. (I keep mine to water plants.)

If you did not keep the old water, you might try charging out some of the water with distilled or purified drinking water. 

If you want to cool the water, you can put ice (or anything frozen in your freezer) into a zip lock bag and put it in the water for short periods of time, while monitoring the temp closely. Cool water hold more oxygen than warm. but changing the temp quickly is hard on the fish.

Peroxide acts like bleach at full strength. It oxidizes and kills germs.  If you were spaying it on the glass to kill algae, maybe too much got into the water.  

I have diluted peroxide and used it to raise oxygen in a water that had low oxygen due to heat. In small dilute amounts it is a life saver for fish that are suffocating. It breaks down into O2 and water.  I've never used it full strength in a fish tank.

 

On 12/26/2021 at 11:08 PM, Gator said:

@eddie462 and @Gideyon; back in the '80's while still living in Orlando, FL, a Guppy Society recommended using Hydrogen Peroxide to increase the oxygen levels in aquariums. On the outside it makes sense since Hydrogen Peroxide is made up of two parts Hydrogen and two parts Oxygen and would bond with those same molecules in the tanks water, but I never did this for the same reason @Gideyon stated, Hydrogen Peroxide may damage the gills of my fish. I do use Hydrogen Peroxide to kill Blackbeard algae, but the dosage is sprayed on the algae, is in a much smaller dose that what was recommended in the '80's, and my water temps do not rise because of it. 

 

On 12/26/2021 at 11:10 PM, RadMax8 said:

How much H2O2 did you add? In my experience, you’ve got to be careful with that, as it can oxidize the gills of the fish (think what happens when you put H2O2 on a cut) and cause irritation or damage. 

Keep an eye on your fish, I would probably do another water change. 

 

On 12/27/2021 at 8:32 AM, Odd Duck said:

I also would suspect the peroxide, but I have used 3% peroxide at up to 3 mls per gallon (based on the actual water volume in the tank, not just based on tank size) with no deleterious side effects to the fish multiple times.  I use this with a full tank with no power filters running (I leave the sponge filters running to have some aeration during treatment) and use a syringe and tubing to “drizzle” the peroxide directly on the algae I want to kill.  Usually I can do a lower dose focused just on small areas of algae.  I leave the power filters off for 10 minutes monitoring closely for any signs of stress in the inhabitants.  Turn the filters back on and run everything as usual.

If your water volume was low during the water change, you have to dose based on the water volume that was actually in the tank at the time or your concentration of peroxide in the water could get much too high and damage gills.

I think you’re doing what you can - aeration and steady temps, tincture of time.

Thank you all for the replies. I added in too much hydrogen peroxide. I think I added in about 100 ml of h202, which was over 3ml per gallon. I knew before hand that h202 breaks down into o2 and water, so I didn’t think there was a maximum dosing amount. It turns out I was wrong. 
 

I lost 2 guppies, 1 nerite snail and one of my penguin tetras isn’t swimming correctly so idk if I can help that fish. I’m missing one guppy and my bn pleco. I have a 3D background so the pleco may be behind it but I can’t see all of the area behind the background. 
 

I feel terrible about these deaths, but now I know to be more aware of h202 dosing amounts. Thank you @KittenFishMom I’m glad that I did try to save them instead of just letting them die.  

[AndEEss]

Slow down and do your research about ANY new process or technique beforehand. Don't just read one source, read several. Consult multiple forums. Watch YouTube. 

Example: I'm going to make acrylic lily pipes to fit the tubing for the FX6 filter I just bought. Why? Because after a number of searches, I concluded that no one makes 1" clear lily pipes, or at least, not at any price I'm willing to pay. So, I have watched half a dozen YouTube videos about the proper way to cut, prepare, heat, bend and shape the tubing. According to my internet history, I've found threads on no less than 5 different online forums about it. 

 

 

[KittenFishMom]

You also admitted that there was a problem and came to the forum with lots of clear details to ask for help.  It is reasonable to feel bad about the loss, but remember you handled the situation very responsibly.  Don't beat yourself up about this, be proud of your ability to keep your head and look for help and ways to improve the situation. No one gets everything right every time.

[Odd Duck]

@eddie462 I think you’ve done what you can, just keep doing what you’re doing.  You DID act quickly as soon as you realized there was an issue.  I’m pretty sure I’ve made every mistake in the book and then some.  Heck, I absolutely TOASTED a heater just a few weeks ago!  I hadn’t done that in DECADES!  And I’ll admit, it took me far too long to figure out what was going on before I acted.  I was lucky there were no fish in the tank.  🤦🏻‍♀️ The house reeked of melted plastic (the heater guard) for well over a week afterwards.

You can only do as much as you know how to do, and you did that, and quickly.  Try not to beat yourself up.  Take it in as a learning experience, move on, and do better the next time since I have no doubt that you will.

Keep up the extra aeration, super clean water, and support your little penguin tetra that way.  It’s all you can do.  Just have patience, there’s still a chance it will snap out of it.  Here’s hoping for the best for you and your little guy.

Edited December 29, 2021 by Odd Duck

[dasaltemelosguy]

I've done the same thing.  I'm so sorry. I added peroxide for that very reason once and killed 26 fish. I still feel guilty. 

@Odd Duck I've melted a few heaters myself!

@eddie462, if you still wish to add Oxygen to the tank, this may be of some help. Good luck.