How safe is Hydrogen Peroxide?

[Byron]

Do not use this if you have live fish in the tank. Nothing should ever be added to the water except what is absolutely essential for the fish. "Safe" these days (at least in the thinking of hobby manufacturers and all too many hobbyists themselves) seems to mean the fish don't immediately expire...but that does not mean the substance is safe.

Hydrogen peroxide is a powerful oxidizer that has been used under field conditions to control I. multifiliis. High doses can cause gill damage leading to fish mortality (especially at high temperatures) (Schmidt et al. 2006; Noga, 2010; Picon-Camcho et al. 2011). I know, some will insist "high doses" means it is OK at low doses...not intelligent thinking when fish are involved.

There is only one safe way to deal with any problem algae, and that is to deal with the cause.

 

[itiwhetu]

Increase your oxygen level on your tank and the algae will disappear. Ways to that are. lower your tank temperature, increase your plant numbers, increase your filtration, increase the air flow via air stones. Algae on grows in oxygen deprived water.

 

[Ichthys]

Increase your oxygen level on your tank and the algae will disappear. Ways to that are. lower your tank temperature, increase your plant numbers, increase your filtration, increase the air flow via air stones. Algae on grows in oxygen deprived water.

Absolutely 100% untrue.

 

[Bruce Leyland-Jones]

Increase your oxygen level on your tank and the algae will disappear. Ways to that are. lower your tank temperature, increase your plant numbers, increase your filtration, increase the air flow via air stones. Algae on grows in oxygen deprived water.

What!?!
No mention of the live plants, reducing waste and duration of light!?!

 

[Ichthys]

Do not use this if you have live fish in the tank. Nothing should ever be added to the water except what is absolutely essential for the fish. "Safe" these days (at least in the thinking of hobby manufacturers and all too many hobbyists themselves) seems to mean the fish don't immediately expire...but that does not mean the substance is safe.

Hydrogen peroxide is a powerful oxidizer that has been used under field conditions to control I. multifiliis. High doses can cause gill damage leading to fish mortality (especially at high temperatures) (Schmidt et al. 2006; Noga, 2010; Picon-Camcho et al. 2011). I know, some will insist "high doses" means it is OK at low doses...not intelligent thinking when fish are involved.

There is only one safe way to deal with any problem algae, and that is to deal with the cause.

If we stopped using everything that was dangerous to fish we would have literally no disease treatments. They’re all dangerous at the wrong dosage. Treating a fish is a compromise. We add dangerous substances at doses that will kill the disease but not kill the fish. H2O2 at the correct dosage for the correct duration is no more dangerous than any other chemical treatment. Targeted spot-treatment using H2O2 is a tried and tested way of killing algae and certain pests such as Hydra.

 

[Byron]

If we stopped using everything that was dangerous to fish we would have literally no disease treatments. They’re all dangerous at the wrong dosage. Treating a fish is a compromise. We add dangerous substances at doses that will kill the disease but not kill the fish. H2O2 at the correct dosage for the correct duration is no more dangerous than any other chemical treatment. Targeted spot-treatment of algae using H2O2 is a tried and tested way of killing algae and certain pests such as Hydra.

You seem to have missed what I said. I wrote that nothing should be added to the water (with fish in the tank) except what is absolutely essential for the betterment of the fish. This will include so-called "treatment" medications, antibiotics, etc. that are not the safest and most effective remedy for the specific "disease" if one is present. There is no way you can argue that hydrogen peroxide is absolutely essential for the health of the fish in the issue before us, so don't use it unless fish are removed.

Too many individuals are too quick to dump chemicals in the tank to "cure" often imaginary "disease." In the last 12 years I have had serious issues only three times, and each was introduced with new fish. One was gill flukes brought in with wild Corydoras fowleri, and the other two were some type of internal protozoan that took several weeks to manifest itself, and upon the direct advice of an online marine biologist friend I treated (very effectively) with metronidazole. If we provide fish with what they need--clean water free of all of these concoctions--they will inevitably be healthier and better able to deal with "x" naturally when something does occur. No one medicates the fishes' habitat waters yet they do not succumb to ich and other issues. And, it is now recognized that 90-95% of all aquarium fish "disease" is directly due to stress which weakens the fish's ability to use its immune system to effectively deal with these things.

 

[Ichthys]

You seem to have missed what I said. I wrote that nothing should be added to the water (with fish in the tank) except what is absolutely essential for the betterment of the fish. This will include so-called "treatment" medications, antibiotics, etc. that are not the safest and most effective remedy for the specific "disease" if one is present. There is no way you can argue that hydrogen peroxide is absolutely essential for the health of the fish in the issue before us, so don't use it unless fish are removed.

Too many individuals are too quick to dump chemicals in the tank to "cure" often imaginary "disease." In the last 12 years I have had serious issues only three times, and each was introduced with new fish. One was gill flukes brought in with wild Corydoras fowleri, and the other two were some type of internal protozoan that took several weeks to manifest itself, and upon the direct advice of an online marine biologist friend I treated (very effectively) with metronidazole. If we provide fish with what they need--clean water free of all of these concoctions--they will inevitably be healthier and better able to deal with "x" naturally when something does occur. No one medicates the fishes' habitat waters yet they do not succumb to ich and other issues. And, it is now recognized that 90-95% of all aquarium fish "disease" is directly due to stress which weakens the fish's ability to use its immune system to effectively deal with these things.

I saw what you said, which is why I replied.

At dosages required for spot-treatment it is quite safe, since it dissociates fairly rapidly.

 

[Bruce Leyland-Jones]

You seem to have missed what I said. I wrote that nothing should be added to the water (with fish in the tank) except what is absolutely essential for the betterment of the fish. This will include so-called "treatment" medications, antibiotics, etc. that are not the safest and most effective remedy for the specific "disease" if one is present. There is no way you can argue that hydrogen peroxide is absolutely essential for the health of the fish in the issue before us, so don't use it unless fish are removed.

Too many individuals are too quick to dump chemicals in the tank to "cure" often imaginary "disease." In the last 12 years I have had serious issues only three times, and each was introduced with new fish. One was gill flukes brought in with wild Corydoras fowleri, and the other two were some type of internal protozoan that took several weeks to manifest itself, and upon the direct advice of an online marine biologist friend I treated (very effectively) with metronidazole. If we provide fish with what they need--clean water free of all of these concoctions--they will inevitably be healthier and better able to deal with "x" naturally when something does occur. No one medicates the fishes' habitat waters yet they do not succumb to ich and other issues. And, it is now recognized that 90-95% of all aquarium fish "disease" is directly due to stress which weakens the fish's ability to use its immune system to effectively deal with these things.

I agree almost 100%, except that;

• Fish in the wild do succumb to ich, internal parasites and external parasites and most of the diseases we see in the aquarium. These complaints weren't invented in aquaria, although they are obviously more apparent within our enclosed ecosystems, where they can actually get treated. In the wild, it is never in a parasite's best interest to kill the host, but fish do die in the wild from the aforementioned. As we know, dead fish quickly disappear in our tanks...they disappear even more quickly in the wild and diseased fish often act as vectors for the original parasite/disease that afflicted them.
• The wild fishes' habitat is never, ever, as pure and free from minerals, etc., as our supplied tapwaters.

 

[Ichthys]

Indeed, all pathogens found in our tanks exist in the wild. Fish get stressed from pollution (natural and man-made), predators that specialise in eating fins, scales, eyes...and other causes.
Diseased fish in the wild usually die from predation, which is why we see them less frequently than in captivity.

 

[Bruce Leyland-Jones]

I remember a series of lectures from a keen aquarist who had visited the Amazon. Much as he had enjoyed the trip, (and who wouldn't), he summed the experience up in one word...disappointment! Apparently, he had been expecting at least some clear waters, but because of the weather, he had seen very, very little. He also disappointed his botany colleagues with his images of the aquatic plants out there, as they were all extremely manky.

 

[Ichthys]

In the main channel of the Amazon and most of its large tributaries visibility is next to zero. Makes me wonder how fish even feed...

 

[Byron]

I am not disputing diseases in wild fish. But the point that must be understood is that fish can deal with these in some form. Nature may use the disease to lower the species numbers, or deal with something else. But the fish will be able to survive, otherwise the species would become extinct. I frequently see an indication that ich is present; there is now thinking that it is present in most all of our aquaria but under control. Keeping the fish stress-free will aid the fish to naturally deal with these issues, 90% or more. Adding any substance that can diffuse across the cell membrane and enter the fish along with the water in the tank is always going to add stress. It is a fact of fish physiology. Avoid the substances and their related stress, and the fish will be the better for it.

 

[Byron]

In the main channel of the Amazon and most of its large tributaries visibility is next to zero. Makes me wonder how fish even feed...

If you really do not know the answer to your own question, I can see how the other issue becomes less understandable. Visibility is only one natural tool fish can use. Their sense of hearing is very acute, more than ours, as is their sense of smell. I had one of the Congo Tetra males go blind many years ago, and it lived in the tank with the other five for a few years.

Too many aquarists are unwilling to research and come to understand the incredible physiological operations of a fish in water, and this is undoubtedly why so many of them lose so many fish. The work of forums like TFF is to provide the knowledge and help.

 

[Bruce Leyland-Jones]

In the main channel of the Amazon and most of its large tributaries visibility is next to zero. Makes me wonder how fish even feed...

Barbels, whiskers and lateral lines.
(But you knew that )

 

[Bruce Leyland-Jones]

I am not disputing diseases in wild fish. But the point that must be understood is that fish can deal with these in some form. Nature may use the disease to lower the species numbers, or deal with something else. But the fish will be able to survive, otherwise the species would become extinct. I frequently see an indication that ich is present; there is now thinking that it is present in most all of our aquaria but under control. Keeping the fish stress-free will aid the fish to naturally deal with these issues, 90% or more. Adding any substance that can diffuse across the cell membrane and enter the fish along with the water in the tank is always going to add stress. It is a fact of fish physiology. Avoid the substances and their related stress, and the fish will be the better for it.

The battle between higher and lower organisms for survival is continuous...and in many instances, it isn't the disease organism that becomes extinct.
I've never accepted the idea that ich is present in all aquaria, just waiting for stressed fish for it to suddenly re-appear. I believe that this is just a rationale made by those who have inadvertently imported it from somewhere else.
Pathological bacteria, on the other hand...